python_2_unicode_compatible error

I've models.py as follows,

from django.contrib.auth.models import Userfrom django.db import modelsfrom django.utils.encoding import python_2_unicode_compatiblefrom django.utils.timezone import now@python_2_unicode_compatibleclass Tag(models.Model):    name = models.CharField(max_length=50, unique=True)    class Meta:            verbose_name = 'tag'            verbose_name_plural = 'tags'            ordering = ['name']    def __str__(self):            return self.name.............  and so on

When I ran python manage.py syncdb this is the error I got:

itman@itman:~/djangoApp/mysite$ python manage.py syncdbTraceback (most recent call last):   File "manage.py", line 10, in <module>    execute_from_command_line(sys.argv)  File "/usr/lib/python2.7/dist-packages/django/core/management/__init__.py", line 443, in execute_from_command_line    utility.execute()  File "/usr/lib/python2.7/dist-packages/django/core/management/__init__.py", line 382, in execute    self.fetch_command(subcommand).run_from_argv(self.argv)  File "/usr/lib/python2.7/dist-packages/django/core/management/base.py", line 196, in run_from_argv    self.execute(*args, **options.__dict__)  File "/usr/lib/python2.7/dist-packages/django/core/management/base.py", line 231, in execute    self.validate()  File "/usr/lib/python2.7/dist-packages/django/core/management/base.py", line 266, in validate    num_errors = get_validation_errors(s, app)  File "/usr/lib/python2.7/dist-packages/django/core/management/validation.py", line 30, in get_validation_errors    for (app_name, error) in get_app_errors().items():  File "/usr/lib/python2.7/dist-packages/django/db/models/loading.py", line 158, in get_app_errors    self._populate()  File "/usr/lib/python2.7/dist-packages/django/db/models/loading.py", line 67, in _populate    self.load_app(app_name)  File "/usr/lib/python2.7/dist-packages/django/db/models/loading.py", line 88, in load_app    models = import_module('.models', app_name)  File "/usr/lib/python2.7/dist-packages/django/utils/importlib.py", line 35, in import_module    __import__(name)  File "/home/itman/djangoApp/mysite/bmark/models.py", line 4, in <module>    from django.utils.encoding import python_2_unicode_compatibleImportError: cannot import name python_2_unicode_compatible

I don't know why the module is not imported. I'm using Python 2.7 and Django 1.4.