maximum recursion depth exceeded in cmp error while executing python manage.py runserver

Question

I'm trying to install Django in my mac. when I run the command python manage.py runserver. I get the error RuntimeError: maximum recursion depth exceeded in cmp. I have pasted my error message below. I even increased the setrecursion limit to 2000 and tried, it didn't work. Any of your help in fixing this is appreciated...

Validating models...

Unhandled exception in thread started by <bound method Command.inner_run of <django.contrib.staticfiles.management.commands.runserver.Command object at 0x1087f4a10>>
Traceback (most recent call last):
  File "/Library/Python/2.7/site-packages/django/core/management/commands/runserver.py", line 92, in inner_run
    self.validate(display_num_errors=True)
  File "/Library/Python/2.7/site-packages/django/core/management/base.py", line 280, in validate
    num_errors = get_validation_errors(s, app)
  File "/Library/Python/2.7/site-packages/django/core/management/validation.py", line 35, in get_validation_errors
    for (app_name, error) in get_app_errors().items():
  File "/Library/Python/2.7/site-packages/django/db/models/loading.py", line 166, in get_app_errors
    self._populate()
  File "/Library/Python/2.7/site-packages/django/db/models/loading.py", line 72, in _populate
    self.load_app(app_name, True)
  File "/Library/Python/2.7/site-packages/django/db/models/loading.py", line 96, in load_app
    models = import_module('.models', app_name)
  File "/Library/Python/2.7/site-packages/django/utils/importlib.py", line 35, in import_module
    __import__(name)
  File "/Library/Python/2.7/site-packages/django/contrib/auth/models.py", line 370, in <module>
    class AbstractUser(AbstractBaseUser, PermissionsMixin):
  File "/Library/Python/2.7/site-packages/django/db/models/base.py", line 213, in __new__
    new_class.add_to_class(field.name, copy.deepcopy(field))
  File "/Library/Python/2.7/site-packages/django/db/models/base.py", line 265, in add_to_class
    value.contribute_to_class(cls, name)
  File "/Library/Python/2.7/site-packages/django/db/models/fields/__init__.py", line 257, in contribute_to_class
    cls._meta.add_field(self)
  File "/Library/Python/2.7/site-packages/django/db/models/options.py", line 179, in add_field
    self.local_fields.insert(bisect(self.local_fields, field), field)
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/functools.py", line 56, in <lambda>
    '__lt__': [('__gt__', lambda self, other: other < self),
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/functools.py", line 56, in <lambda>
    '__lt__': [('__gt__', lambda self, other: other < self),
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/functools.py", line 56, in <lambda>
    '__lt__': [('__gt__', lambda self, other: other < self),
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/functools.py", line 56, in <lambda>
    '__lt__': [('__gt__', lambda self, other: other < self),
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/functools.py", line 56, in <lambda>
    '__lt__': [('__gt__', lambda self, other: other < self),
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/functools.py", line 56, in <lambda>
    '__lt__': [('__gt__', lambda self, other: other < self),
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/functools.py", line 56, in <lambda>
    '__lt__': [('__gt__', lambda self, other: other < self),
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/functools.py", line 56, in <lambda>
    '__lt__': [('__gt__', lambda self, other: other < self),
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/functools.py", line 56, in <lambda>
 File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/functools.py", line 56, in <lambda>
    '__lt__': [('__gt__', lambda self, other: other < self),
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/functools.py", line 56, in <lambda>
    '__lt__': [('__gt__', lambda self, other: other < self),
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/functools.py", line 56, in <lambda>
    '__lt__': [('__gt__', lambda self, other: other < self),
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/functools.py", line 56, in <lambda>
    '__lt__': [('__gt__', lambda self, other: other < self),
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/functools.py", line 56, in <lambda>
    '__lt__': [('__gt__', lambda self, other: other < self),
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/functools.py", line 56, in <lambda>
    '__lt__': [('__gt__', lambda self, other: other < self),
RuntimeError: maximum recursion depth exceeded in cmp

Answer 1

The problem is in functools.py file. This file is from Python. I have just installed a new version of python 2.7.5 and the file is wrong (I have another older instalation of python 2.7.5 and ther the file functools.py is correct)

To fix the problem replace this (about line 56 in python\\Lib\\fuctools.py):

    convert = {
    '__lt__': [('__gt__', lambda self, other: other < self),
               ('__le__', lambda self, other: not other < self),
               ('__ge__', lambda self, other: not self < other)],
    '__le__': [('__ge__', lambda self, other: other <= self),
               ('__lt__', lambda self, other: not other <= self),
               ('__gt__', lambda self, other: not self <= other)],
    '__gt__': [('__lt__', lambda self, other: other > self),
               ('__ge__', lambda self, other: not other > self),
               ('__le__', lambda self, other: not self > other)],
    '__ge__': [('__le__', lambda self, other: other >= self),
               ('__gt__', lambda self, other: not other >= self),
               ('__lt__', lambda self, other: not self >= other)]
}

to that:

    convert = {
    '__lt__': [('__gt__', lambda self, other: not (self < other or self == other)),
               ('__le__', lambda self, other: self < other or self == other),
               ('__ge__', lambda self, other: not self < other)],
    '__le__': [('__ge__', lambda self, other: not self <= other or self == other),
               ('__lt__', lambda self, other: self <= other and not self == other),
               ('__gt__', lambda self, other: not self <= other)],
    '__gt__': [('__lt__', lambda self, other: not (self > other or self == other)),
               ('__ge__', lambda self, other: self > other or self == other),
               ('__le__', lambda self, other: not self > other)],
    '__ge__': [('__le__', lambda self, other: (not self >= other) or self == other),
               ('__gt__', lambda self, other: self >= other and not self == other),
               ('__lt__', lambda self, other: not self >= other)]
}

Answer 2

If you haven't already, try installing python 2.7.5

I had a similar issue when using django version 1.5.1 and python version 2.7.2. The issue was resolved when I switched to 2.7.5.

To get python 2.7.5 running on your mac, go here and download the Mac Installer for your system. After installing, go to the "Python 2.7" subfolder of the system Applications folder, and double-click on the "Update Shell Profile" to use 2.7.5 from the command line.

After doing that, type python --version from the command line to confirm you're using 2.7.5

Hope that helps!

Answer 3

I encountered the same problem right after starting a new project without any coding.

There was a similar post here .

In my case, I just had to uninstall and then install django again.

sudo pip uninstall django

sudo pip install django

One caution. I performed this operation in new terminal. After installation, I went back to the terminal where I got the error and run "python manage.py runserver", I still got the same error but on a new terminal window, it didn't give me error.

Hope this works for you.

Answer 4

have you run syncdb yet? maybe try using sqllite to make sure that the problem isn't related to the mysqldb package?

Answer 5

Make sure you start the python shell using the command :

$ python manage.py shell

in order to load the correct settings. I was facing the same problem but I realized I was starting the shell by just using :

$ python

A good explanation for this can be found here in the submission by Pavel Anossov : Django DB Settings 'Improperly Configured' Error

Answer 6

I had faced this error just because I tried to run the migrate command directly after creating the new project.
Then I created a new project , runserver first and then run the migrate command , It will work.