tofigureout: Django apps prefix

If all of all my Django apps are in the "apps" dir, is there something I can set so that I can directly write the app name instead of "apps.app_name" everytime.

It seems like I can do this only with sys.path or PYTHONPATH, which applies to all the django projects in the environment. This doesn't seem like a satisfactory solution. ... my summer project MozSecWorld didn't have this problem, I wonder what magic the setup for that did.

Setting up new Django project (with virtualenv(wrapper))

Download Django for Ubuntu in root:

1. cd /usr/local/lib, mkdir django-1.3.1 and cd into it

2a. wget http://www.djangoproject.com/download/1.3.1/tarball/ -O Django-1.3.1.tar.gz, got this step from here

2b. cd Django-1.3.1.tar.gz

2c. sudo python setup.py install

So my Django path is:

/usr/local/lib/django-1.3.1/Django-1.3.1

In user:
1. mkvirtualenv --no-site-packages vocab this is virtualenvwrapper setting up a new environment. Setup is logged in this old post.

$ mkvirtualenv --no-site-packages vocab
New python executable in vocab/bin/python
Installing setuptools............done.
Installing pip...............done.
virtualenvwrapper.user_scripts creating /home/my_username/.virtualenvs/vocab/bin/predeactivate
virtualenvwrapper.user_scripts creating /home/my_username/.virtualenvs/vocab/bin/postdeactivate
virtualenvwrapper.user_scripts creating /home/my_username/.virtualenvs/vocab/bin/preactivate
virtualenvwrapper.user_scripts creating /home/my_username/.virtualenvs/vocab/bin/postactivate
virtualenvwrapper.user_scripts creating /home/my_username/.virtualenvs/vocab/bin/get_env_details
mkdir: cannot create directory `/home/my_username/Projects/vocab': No such file or directory
-bash: cd: /home/my_username/Projects/vocab: No such file or directory
Searching for readline
Reading http://pypi.python.org/simple/readline/
Reading http://www.python.org/
Reading http://github.com/ludwigschwardt/python-readline
Best match: readline 6.2.1
Downloading http://pypi.python.org/packages/source/r/readline/readline-6.2.1.tar.gz#md5=9604527863378512247fcaf938100797
Processing readline-6.2.1.tar.gz
Running readline-6.2.1/setup.py -q bdist_egg --dist-dir /tmp/easy_install-9h67Mv/readline-6.2.1/egg-dist-tmp-nNoSrj
/usr/bin/ld: cannot find -lncurses
collect2: ld returned 1 exit status
error: Setup script exited with error: command 'gcc' failed with exit status 1
Downloading/unpacking Jinja2==2.3.1
  Downloading Jinja2-2.3.1.tar.gz (428Kb): 428Kb downloaded
  Running setup.py egg_info for package Jinja2
    
    warning: no previously-included files matching '*' found under directory 'docs/_build/doctrees'
Downloading/unpacking MySQL-python==1.2.3c1
  Downloading MySQL-python-1.2.3c1.tar.gz (89Kb): 89Kb downloaded
  Running setup.py egg_info for package MySQL-python
    
Downloading/unpacking lxml==2.2.6
  Downloading lxml-2.2.6.tar.gz (2.9Mb): 2.9Mb downloaded
  Running setup.py egg_info for package lxml
    Building lxml version 2.2.6.
    NOTE: Trying to build without Cython, pre-generated 'src/lxml/lxml.etree.c' needs to be available.
    ERROR: /bin/sh: xslt-config: not found
    
    ** make sure the development packages of libxml2 and libxslt are installed **
    
    Using build configuration of libxslt
    
    warning: no previously-included files found matching '*.py'
Downloading/unpacking PIL
  Downloading PIL-1.1.7.tar.gz (506Kb): 506Kb downloaded
  Running setup.py egg_info for package PIL
    WARNING: '' not a valid package name; please use only.-separated package names in setup.py
    
Obtaining check from git+git://github.com/jbalogh/check.git#egg=check
  Cloning git://github.com/jbalogh/check.git to /home/my_username/.virtualenvs/vocab/src/check
  Running setup.py egg_info for package check
    
Downloading/unpacking pyflakes (from check)
  Downloading pyflakes-0.5.0.tar.gz
  Running setup.py egg_info for package pyflakes
    
Downloading/unpacking pep8 (from check)
  Downloading pep8-0.6.1.tar.gz
  Running setup.py egg_info for package pep8
    
Downloading/unpacking path.py (from check)
  Error  while getting http://pypi.python.org/packages/source/p/path.py/path.py-2.2.2.tar.gz#md5=3a3262b9049d294ddbd6f7453d45e699 (from http://pypi.python.org/simple/path.py/)
Exception:
Traceback (most recent call last):
  File "/home/my_username/.virtualenvs/vocab/local/lib/python2.7/site-packages/pip-1.0.2-py2.7.egg/pip/basecommand.py", line 126, in main
    self.run(options, args)
  File "/home/my_username/.virtualenvs/vocab/local/lib/python2.7/site-packages/pip-1.0.2-py2.7.egg/pip/commands/install.py", line 223, in run
    requirement_set.prepare_files(finder, force_root_egg_info=self.bundle, bundle=self.bundle)
  File "/home/my_username/.virtualenvs/vocab/local/lib/python2.7/site-packages/pip-1.0.2-py2.7.egg/pip/req.py", line 961, in prepare_files
    self.unpack_url(url, location, self.is_download)
  File "/home/my_username/.virtualenvs/vocab/local/lib/python2.7/site-packages/pip-1.0.2-py2.7.egg/pip/req.py", line 1079, in unpack_url
    return unpack_http_url(link, location, self.download_cache, only_download)
  File "/home/my_username/.virtualenvs/vocab/local/lib/python2.7/site-packages/pip-1.0.2-py2.7.egg/pip/download.py", line 429, in unpack_http_url
    resp = _get_response_from_url(target_url, link)
  File "/home/my_username/.virtualenvs/vocab/local/lib/python2.7/site-packages/pip-1.0.2-py2.7.egg/pip/download.py", line 465, in _get_response_from_url
    resp = urlopen(target_url)
  File "/home/my_username/.virtualenvs/vocab/local/lib/python2.7/site-packages/pip-1.0.2-py2.7.egg/pip/download.py", line 84, in __call__
    response = urllib2.urlopen(self.get_request(url))
  File "/usr/lib/python2.7/urllib2.py", line 126, in urlopen
    return _opener.open(url, data, timeout)
  File "/usr/lib/python2.7/urllib2.py", line 391, in open
    response = self._open(req, data)
  File "/usr/lib/python2.7/urllib2.py", line 409, in _open
    '_open', req)
  File "/usr/lib/python2.7/urllib2.py", line 369, in _call_chain
    result = func(*args)
  File "/usr/lib/python2.7/urllib2.py", line 1185, in http_open
    return self.do_open(httplib.HTTPConnection, req)
  File "/usr/lib/python2.7/urllib2.py", line 1160, in do_open
    raise URLError(err)
URLError: 

Storing complete log in /home/my_username/.pip/pip.log

2. Since I installed with no-site-packages, I need to add Django to the virtualenv
add2virtualenv /usr/local/lib/django-1.3.1/Django-1.3.1

3. follow the Django tutorial

3b. In python manage.py sql app_name I got this error:

...
raise ImproperlyConfigured("Error loading MySQLdb module: %s" % e)
django.core.exceptions.ImproperlyConfigured: Error loading MySQLdb module: No module named MySQLdb

so I did
pip install MySQL-python

3c. I installed my app inside an "apps" folder, so here is what I did:
mkdir apps; touch apps/__init__.py
python manage.py startapp app_name
mv app_name apps
vim settings.py and add into INSTALLED_APPS 'apps.apps_name'
python manage.py sql app_name
Note that you should have 'apps.app_name' in INSTALLED_APPS or else it's not going to find it and give you this error instead:

Error: No module named app_name

Setting up MSW on Rackspace

./manage.py shell

django.core.exceptions.ImproperlyConfigured: Error loading MySQLdb module: No module named MySQLdb

In root install: pip install mysql-python.

If you I got another error ...

In file included from _mysql.c:29:0:
pymemcompat.h:10:20: fatal error: Python.h: No such file or directory
compilation terminated.
error: command 'gcc' failed with exit status 1

... then you need to install sudo apt-get install python-dev

(I searched for solutions for a long time, trying to find my "/usr/local/mysql" on ubuntu, but I don't have it (even though I have mysql).)


Now ./manage.py shell has

ImportError: No module named OpenSSL

From root, pip install pyopenssl


Now ./manage.py shell has

ImportError: No module named bycrypt

From root, pip install py-bcrypt

AND THEN I GOT MANAGE.PY SHELL!!!
import django! works on it too!!!!!!!!

$ ./manage.py shell
Python 2.7.1+ (r271:86832, Apr 11 2011, 18:13:53) 
[GCC 4.5.2] on linux2
Type "help", "copyright", "credits" or "license" for more information.
(InteractiveConsole)
>>> import django

Whoa I can even run it on my rackspace IP! :D Even though it crashes, at least it can get the request!

$ ./manage.py runserver 50.57.147.82:8000
Validating models...

0 errors found
Django version 1.3.1, using settings 'MozSecWorld.settings_local'
Development server is running at http://50.57.147.82:8000/
Quit the server with CONTROL-C.
[21/Oct/2011 03:23:36] "GET / HTTP/1.1" 301 0

Traceback (most recent call last):
...
TemplateSyntaxError: Caught ImportError while rendering: No module named jinja2
[21/Oct/2011 03:23:37] "GET /msw/ HTTP/1.1" 500 2909

So I did, from root, pip install jinja2

AND MOZSECWORLD IS UP at http://50.57.147.82:8000/!!!!!!!! :D:D:D

Django vendor-local adding package

playdoh (master)$ pip install --no-install --build=vendor-local/packages --src=vendor-local/src -I django-csp
Downloading/unpacking django-csp
  Downloading django_csp-1.0.2.tar.gz
  Running setup.py egg_info for package django-csp

which installed django-csp into vendor-local/packages

and then I added the path to vendor-local/vendor.pth:

packages/django-csp

FYI, the contents:

playdoh/vendor-local/packages/django-csp (master)$ ls -R
PKG-INFO            django_csp.egg-info setup.cfg
csp                 pip-egg-info        setup.py

./csp:
__init__.py   decorators.py middleware.py urls.py       views.py

./django_csp.egg-info:
PKG-INFO             dependency_links.txt
SOURCES.txt          top_level.txt

./pip-egg-info:
django_csp.egg-info

./pip-egg-info/django_csp.egg-info:
PKG-INFO             dependency_links.txt
SOURCES.txt          top_level.txt

The Resource

Python Check.py!

pip install -e git://github.com/jbalogh/check.git#egg=check

Pip Install Django Debug Toolbar

pip install django-debug-toolbar

So you get to do python manage.py debugsqlshell and have a debug sidebar.

It's awesome

Pypi

Randomizing in Django QuerySet and Python List

Django QuerySet:

my_queryset.order_by('?')

Python List:

import random

random.shuffle(my_list)

And then you can use slice to just keep n elements, e.g.

n = 5
my_queryset.order_by('?')[:n]

Django "MultipleObjectsReturned: get() returned more than one" fix with filter()

get() returns single objects. so use filter() instead.

Django get user object in views.py

In views.py

def index(request):
    # get user
    try:
        the_user = User.objects.get(username = request.user)
    except User.DoesNotExist:
        return HttpResponse("Invalid username")

How adopted-kitsune Django upload works.

0. forms.py

class ImageAttachmentUploadForm(forms.Form):

    """Image upload form."""

    print "############################in form"

    image = forms.ImageField(error_messages={'required': MSG_IMAGE_REQUIRED,

                                             'max_length': MSG_IMAGE_LONG},

                             max_length=settings.MAX_FILENAME_LENGTH)

1. views.py

for fileupload page if request.method == 'POST':
    form = forms.ImageAttachmentUploadForm(request.POST, request.FILES)
    if form.is_valid()

2. playdoh/vendor/src/django/django/forms/fields.py

class ImageField(FileField):
    def to_python(self, data):

        """
        Checks that the file-upload field data contains a valid image (GIF, JPG,
        PNG, possibly others -- whatever the Python Imaging Library supports).
        """

Getting Image Upload to work on Django

Learned form r1cky that jpeg and PIL are packages that need to be recompiled for other people, especially those on different operating systems

haoqili: how can I tell if a package needs to be recompiled on the VM or not?
r1cky: hmm, that is a good question. if it is only .py source files then it doesnt need compiling
r1cky: but some libraries have C in them
r1cky: the ones that we use that need compiling are
r1cky: MySQL-python, Jinja2, PIL, lxml
r1cky: and the jpeg one
r1cky: those are installed separately (not copied into the repository)

1. Install PIL into my vendor-local

playdoh (master)$  pip install -I --install-option="--home=`pwd`/vendor-local" pil
Downloading/unpacking pil
  Downloading PIL-1.1.7.tar.gz (506Kb): 506Kb downloaded
  Running setup.py egg_info for package pil
    WARNING: '' not a valid package name; please use only.-separated package names in setup.py
    WARNING: '' not a valid package name; please use only.-separated package names in setup.py
    
Installing collected packages: pil
  Running setup.py install for pil
    WARNING: '' not a valid package name; please use only.-separated package names in setup.py
    WARNING: '' not a valid package name; please use only.-separated package names in setup.py
    --- using frameworks at /System/Library/Frameworks
    building '_imaging' extension
    /usr/bin/cc -fno-strict-aliasing -O3 -w -pipe -DNDEBUG -g -fwrapv -O3 -Wall -Wstrict-prototypes -DHAVE_LIBZ -I/System/Library/Frameworks/Tcl.framework/Headers -I/System/Library/Frameworks/Tk.framework/Headers -IlibImaging -I/Users/haoqili/.virtualenvs/playdoh/include -I/usr/local/include -I/usr/include -I/usr/local/Cellar/python/2.7.1/include/python2.7 -c _imaging.c -o build/temp.macosx-10.4-x86_64-2.7/_imaging.o
    ...
    /usr/bin/cc -L/usr/local/Cellar/readline/6.2.1/lib -bundle -undefined dynamic_lookup -L/usr/local/Cellar/readline/6.2.1/lib build/temp.macosx-10.4-x86_64-2.7/_imagingmath.o -L/usr/local/lib -L/Users/haoqili/.virtualenvs/playdoh/lib -L/usr/lib -o build/lib.macosx-10.4-x86_64-2.7/_imagingmath.so
    --------------------------------------------------------------------
    PIL 1.1.7 SETUP SUMMARY
    --------------------------------------------------------------------
    version       1.1.7
    platform      darwin 2.7.1 (r271:86832, Jun  6 2011, 13:57:48)
                  [GCC 4.2.1 (Apple Inc. build 5666) (dot 3)]
    --------------------------------------------------------------------
    --- TKINTER support available
    *** JPEG support not available
    --- ZLIB (PNG/ZIP) support available
    *** FREETYPE2 support not available
    *** LITTLECMS support not available
    --------------------------------------------------------------------
    To add a missing option, make sure you have the required
    library, and set the corresponding ROOT variable in the
    setup.py script.
    
    To check the build, run the selftest.py script.
    changing mode of build/scripts-2.7/pilconvert.py from 644 to 755
    changing mode of build/scripts-2.7/pildriver.py from 644 to 755
    changing mode of build/scripts-2.7/pilfile.py from 644 to 755
    changing mode of build/scripts-2.7/pilfont.py from 644 to 755
    changing mode of build/scripts-2.7/pilprint.py from 644 to 755
    
    changing mode of /Users/haoqili/dev/playdoh/playdoh/playdoh/vendor-local/bin/pilconvert.py to 755
    changing mode of /Users/haoqili/dev/playdoh/playdoh/playdoh/vendor-local/bin/pildriver.py to 755
    changing mode of /Users/haoqili/dev/playdoh/playdoh/playdoh/vendor-local/bin/pilfile.py to 755
    changing mode of /Users/haoqili/dev/playdoh/playdoh/playdoh/vendor-local/bin/pilfont.py to 755
    changing mode of /Users/haoqili/dev/playdoh/playdoh/playdoh/vendor-local/bin/pilprint.py to 755
Successfully installed pil
Cleaning up...

2. Trying to get JPEG to be supported:

playdoh/vendor-local (master)$ brew install jpeg
Warning: Xcode is not installed! Builds may fail!
==> Downloading http://www.ijg.org/files/jpegsrc.v8c.tar.gz
######################################################################## 100.0%
==> ./configure --prefix=/usr/local/Cellar/jpeg/8c --disable-dependency-tracking
==> make install
/usr/local/Cellar/jpeg/8c: 17 files, 1.6M, built in 13 seconds

3. Rebuild PIL

)$ pip install PIL==1.1.7 --upgrade
Downloading/unpacking PIL==1.1.7
  Downloading PIL-1.1.7.tar.gz (506Kb): 506Kb downloaded
  Running setup.py egg_info for package PIL
    WARNING: '' not a valid package name; please use only.-separated package names in setup.py
    WARNING: '' not a valid package name; please use only.-separated package names in setup.py
    
Installing collected packages: PIL
  Found existing installation: PIL 1.1.7
    Uninstalling PIL:
      Successfully uninstalled PIL
  Running setup.py install for PIL
    WARNING: '' not a valid package name; please use only.-separated package names in setup.py
    WARNING: '' not a valid package name; please use only.-separated package names in setup.py
    --- using frameworks at /System/Library/Frameworks
    building '_imaging' extension
    /usr/bin/cc -fno-strict-aliasing -O3 -w -pipe -DNDEBUG -g -fwrapv -O3 -Wall -Wstrict-prototypes -DHAVE_LIBJPEG -DHAVE_LIBZ -I/System/Library/Frameworks/Tcl.framework/Headers -I/System/Library/Frameworks/Tk.framework/Headers -IlibImaging -I/Users/haoqili/.virtualenvs/playdoh/include -I/usr/local/include -I/usr/include -I/usr/local/Cellar/python/2.7.1/include/python2.7 -c _imaging.c -o build/temp.macosx-10.4-x86_64-2.7/_imaging.o
    ...
    /usr/bin/cc -L/usr/local/Cellar/readline/6.2.1/lib -bundle -undefined dynamic_lookup -L/usr/local/Cellar/readline/6.2.1/lib build/temp.macosx-10.4-x86_64-2.7/_imagingmath.o -L/usr/local/lib -L/Users/haoqili/.virtualenvs/playdoh/lib -L/usr/lib -o build/lib.macosx-10.4-x86_64-2.7/_imagingmath.so
    --------------------------------------------------------------------
    PIL 1.1.7 SETUP SUMMARY
    --------------------------------------------------------------------
    version       1.1.7
    platform      darwin 2.7.1 (r271:86832, Jun  6 2011, 13:57:48)
                  [GCC 4.2.1 (Apple Inc. build 5666) (dot 3)]
    --------------------------------------------------------------------
    --- TKINTER support available
    --- JPEG support available
    --- ZLIB (PNG/ZIP) support available
    *** FREETYPE2 support not available
    *** LITTLECMS support not available
    --------------------------------------------------------------------
    To add a missing option, make sure you have the required
    library, and set the corresponding ROOT variable in the
    setup.py script.
    
    To check the build, run the selftest.py script.
    changing mode of build/scripts-2.7/pilconvert.py from 644 to 755
    changing mode of build/scripts-2.7/pildriver.py from 644 to 755
    changing mode of build/scripts-2.7/pilfile.py from 644 to 755
    changing mode of build/scripts-2.7/pilfont.py from 644 to 755
    changing mode of build/scripts-2.7/pilprint.py from 644 to 755
    
    changing mode of /Users/haoqili/.virtualenvs/playdoh/bin/pilconvert.py to 755
    changing mode of /Users/haoqili/.virtualenvs/playdoh/bin/pildriver.py to 755
    changing mode of /Users/haoqili/.virtualenvs/playdoh/bin/pilfile.py to 755
    changing mode of /Users/haoqili/.virtualenvs/playdoh/bin/pilfont.py to 755
    changing mode of /Users/haoqili/.virtualenvs/playdoh/bin/pilprint.py to 755
Successfully installed PIL
Cleaning up...

Django Playdoh Package Locations

I was confused when reading how to add packages and seeing that packages live in different locations.

jsocol clarified:

/packages is old-and-busted, use lib/python for non-git things
but you can't put any libraries with compiled components into the vendor lib (it means vendor can't contain anything with c/c++ components)
it's just a question of installing via git (or, well, pip install vcs+vcs://) or using PyPI and the name (e.g. "pip install foo")


pip install foo gives vendor-local/lib/python/foo

using git to install foo gives vendor-local/src/foo

---

This is what I did, with help from groovecoder. :D

playdoh (master)$ pip install --no-install --build=vendor-local/packages --src=vendor-local/src -I cef
Downloading/unpacking cef
  Downloading cef-0.2.tar.gz
  Running setup.py egg_info for package cef
    
Successfully downloaded cef

And then I found that cef is inside vendor-local/packages. :D

Now I need to add this path to vendor.pth. Groovecoder told me that "*.pth files are automatically included by the python interpreter"

playdoh/vendor-local (master)$ cat vendor.pth 
packages/cef

Now I can use cef!

playdoh (master)$ python manage.py shell
...
>>> from cef import log_cef
>>>

I could also have done

/playdoh (master)$ pip install -I --install-option="--home=`pwd`/vendor-local" cef
Downloading/unpacking cef
  Downloading cef-0.2.tar.gz
  Running setup.py egg_info for package cef
    
Installing collected packages: cef
  Running setup.py install for cef
    
Successfully installed cef
Cleaning up...

and have

playdoh/vendor-local/lib/python (master)$ ls
cef-0.2-py2.7.egg-info cef.py                 cef.pyc

Django urls, best practice

First iteration:
template html:

<a href="/msw/{{ page.slug }}/">back</a><

---

Second iteration:
template html:

<a href="{{ url('detail', 'richtext_and_safe_url') }}">back</a>

with
urls.py:

url(r'^(?P<input_slug>\w+)/$', views.detail, name='detail')

---

Third (best) iteration
template html:

<h1><a href="{{ page.reverse_url() }}">back</a></h1>

in models.py:

class Page(models.Model):
    slug = models.SlugField() # another way
    ....
    def reverse:_url(self):
        return reverse('detail', args=[self.slug])
        #return reverse('detail', args=['richtext_and_safe_url']) # hard coded way

be sure to pass in "page" in your views.py

inspiration

Django debug

import pdb; pdb.set_trace()

Django preview database query/queries before they are performed

python manage.py sqlall [app name]

Django shell add user permissions and group permissions

Django doc

1. Start the shell, go to your maange.py

>>> python manage.py shell

2. Get the user

Either load one ...

>>> from django.contrib.auth import authenticate
>>> user = authenticate(username="johndoe", password="yourpw")

Or create one ...

>>> from django.contrib.auth.models import User
>>> user = User.objects.create_user(username='johndoe', email="",  password="yourpw")

Django should silently automatically save it, and you should see it under Users in your admin page. But if you want save it yourself, do:

>>> user.is_staff = False
>>> user.save

3. Check the user's permissions

user.get_all_permissions()

or

user.user_permissions.all()

---

1. Start the shell, go to your maange.py

>>> python manage.py shell

2. Create the group

>>> from django.contrib.auth.models import Group
>>> group = Group(name="GroupName")
>>> group.save()

NOTE that Django pre-made permissions are only suggestions, they only go as far as their string names. YOU have to implement them if you want to use them.

Django reference/link to media/js from apps/myapp/views.py

I had to change a javascript file in media/js/my.js on every refresh of a page (apps/myapp/views.py), the path to open that js file is: f = open('media/js/my.js', 'r+').

See a live demo of this here.

Google recaptcha with CSP, hosting javascript locally

I display google's recaptcha from google's recaptcha javascript hosted on my own server after a little manipulation (since I have CSP turned on, I have to bypass the in-body script and setInterval). But I still need to ping google every time for a new challenge.

1. So I saved my domain's equivalent of the RecaptchaState javascript medai/js/google/recState.js.

2. Refresh this file in views.py's by calling this function:

def recaptchaRefresh():
    # get the Recaptcha state.
    url = "https://www.google.com/recaptcha/api/challenge?k=%s" % settings.RECAPTCHA_PUBLIC_KEY
    resock = urllib.urlopen(url)
    data = resock.read()
    resock.close()

    # extract the recaptcha state part of the string
    docloc = data.find("document.write")

    recaptchaState = data[:docloc]

    f = open('media/js/google/recState.js', 'r+')
    f.write(recaptchaState)
    f.close()

3. Copy paste recaptcha.js and make the following changes for CSP compatibility:

3.1 CSP blocks setIntervals that takes string parameters, so change it into a function:

//Recaptcha.timer_id = setInterval("Recaptcha.reload('t');", (a.timeout - 300) * 1E3) 
// -->
Recaptcha.timer_id = setInterval( function() {Recaptcha.reload('t'); }, (a.timeout - 300) * 1E3)

3.2 CSP blocks in-body javascript, host it externally

//} else document.write('<div id="recaptcha_widget_div" style="display:none"></div>'), document.write('<script>Recaptcha.widget = Recaptcha.$("recaptcha_widget_div"); Recaptcha.challenge_callback();<\/script>');
// -->
} else document.write('<div id="recaptcha_widget_div" style="display:none"></div>'), document.write('<script src="http://haoqili.scripts.mit.edu/js/test3.js"><\/script>');

where http://haoqili.scripts.mit.edu/js/test3.js has "Recaptcha.widget = Recaptcha.$("recaptcha_widget_div"); Recaptcha.challenge_callback();"

4. and in your template.html include the javascript from step 2 and 3.

5. Change your settings.py's CSP policies to have "http[s]://www.google.com" allowed in many places. See example

Find where a module is

Run python manage.py shell.
Import captcha.fields
help(captcha.fields) or captcha.__file__ or captcha.fields shown below

    In [3]: import captcha.fields
     
    In [4]: captcha.fields?
    Type:      module
    Base Class:     <type 'module'>
    String Form:    <module 'captcha.fields' from '/Users/jbalogh/dev/zamboni/vendor/src/django-recaptcha/captcha/fields.pyc'>
    Namespace:      Interactive
    File:      /Users/uname/dev/zamboni/vendor/src/django-recaptcha/captcha/fields.py
    Docstring:
        <no docstring> 

It's actually here: django-recaptcha already done before!!, not here. I wish I had know that the django-recaptcha existed before I did this.

How Django form calls clean() method

I was reading the Django docs on forms which says:
Validation of a Form is split into several steps ... [calls]
- [1] to_python()
- [2] validate()
- [3] run_validators()
- [4] clean()
- [5] clean_()

This is how these things work in the source code:

1. each field's clean() method takes care of the first 3 items

# src/django/django/forms/fields.py, comments mine

    class Field(object):
        ...
        def clean(self, value):
            """
            Validates the given value and returns its "cleaned" value as an
            appropriate Python object.

            Raises ValidationError for any errors.
            """
            value = self.to_python(value)    # [1]
            self.validate(value)             # [2]
            self.run_validators(value)       # [3]
            return value

2. aoeu

# src/django/django/forms/fields.py, comments mine

    class BaseForm(StrAndUnicode):
        ...
        def full_clean(self):
            """
            Cleans all of self.data and populates self._errors and
            self.cleaned_data.
            """
            self._errors = ErrorDict()
            if not self.is_bound: # Stop further processing.
                return
            self.cleaned_data = {}
            # If the form is permitted to be empty, and none of the form data has
            # changed from the initial data, short circuit any validation.
            if self.empty_permitted and not self.has_changed():
                return
            self._clean_fields()
            self._clean_form()
            self._post_clean()
            if self._errors:
                del self.cleaned_data

        def _clean_fields(self):
            for name, field in self.fields.items():
                # value_from_datadict() gets the data from the data dictionaries.
                # Each widget type knows how to retrieve its own data, because some
                # widgets split data over several HTML fields.
                value = field.widget.value_from_datadict(self.data, self.files, self.add_prefix(name))
                try:
                    if isinstance(field, FileField):
                        initial = self.initial.get(name, field.initial)
                        # calls step 1's stuff
                        value = field.clean(value, initial) 
                    else:
                        value = field.clean(value)
                    self.cleaned_data[name] = value
                    if hasattr(self, 'clean_%s' % name):
                        value = getattr(self, 'clean_%s' % name)()
                        self.cleaned_data[name] = value
                except ValidationError, e:
                    self._errors[name] = self.error_class(e.messages)
                    if name in self.cleaned_data:
                        del self.cleaned_data[name]

... calls some alias ...
figure it out yourself