Hi Folks, I have build a realtime notification app using Django(1.8.5). I am using django server, Nodejs as push server, ishout.js[nodejs+redis +express.js API]. So I installed them by following the instructions. Kindly suggest how following errors can be fixed : Error:1). Now when I am doing "$ python manage.py shell" , i get this error http://…

server setup

(global)aruns (master *) realtimenotif $ python manage.py shell
Python 2.7.6 (default, Jun 22 2015, 17:58:13) 
[GCC 4.8.2] on linux2
Type "help", "copyright", "credits" or "license" for more information.
(InteractiveConsole)
>>> from django.contrib.auth.models import User
>>> u = User(first_name="Arun",username='arun').save()
Traceback (most recent call last):
  File "<console>", line 1, in <module>
  File "/home/aruns/global/local/lib/python2.7/site-packages/django/db/models/base.py", line 734, in save
    force_update=force_update, update_fields=update_fields)
  File "/home/aruns/global/local/lib/python2.7/site-packages/django/db/models/base.py", line 762, in save_base
    updated = self._save_table(raw, cls, force_insert, force_update, using, update_fields)
  File "/home/aruns/global/local/lib/python2.7/site-packages/django/db/models/base.py", line 846, in _save_table
    result = self._do_insert(cls._base_manager, using, fields, update_pk, raw)
  File "/home/aruns/global/local/lib/python2.7/site-packages/django/db/models/base.py", line 885, in _do_insert
    using=using, raw=raw)
  File "/home/aruns/global/local/lib/python2.7/site-packages/django/db/models/manager.py", line 127, in manager_method
    return getattr(self.get_queryset(), name)(*args, **kwargs)
  File "/home/aruns/global/local/lib/python2.7/site-packages/django/db/models/query.py", line 920, in _insert
    return query.get_compiler(using=using).execute_sql(return_id)
  File "/home/aruns/global/local/lib/python2.7/site-packages/django/db/models/sql/compiler.py", line 974, in execute_sql
    cursor.execute(sql, params)
  File "/home/aruns/global/local/lib/python2.7/site-packages/django/db/backends/utils.py", line 79, in execute
    return super(CursorDebugWrapper, self).execute(sql, params)
  File "/home/aruns/global/local/lib/python2.7/site-packages/django/db/backends/utils.py", line 64, in execute
    return self.cursor.execute(sql, params)
  File "/home/aruns/global/local/lib/python2.7/site-packages/django/db/utils.py", line 97, in __exit__
    six.reraise(dj_exc_type, dj_exc_value, traceback)
  File "/home/aruns/global/local/lib/python2.7/site-packages/django/db/backends/utils.py", line 64, in execute
    return self.cursor.execute(sql, params)
  File "/home/aruns/global/local/lib/python2.7/site-packages/django/db/backends/sqlite3/base.py", line 318, in execute
    return Database.Cursor.execute(self, query, params)
IntegrityError: UNIQUE constraint failed: auth_user.username
>>> u = User(first_name="Arun",username='admin').save()
Traceback (most recent call last):
  File "<console>", line 1, in <module>
  File "/home/aruns/global/local/lib/python2.7/site-packages/django/db/models/base.py", line 734, in save
    force_update=force_update, update_fields=update_fields)
  File "/home/aruns/global/local/lib/python2.7/site-packages/django/db/models/base.py", line 762, in save_base
    updated = self._save_table(raw, cls, force_insert, force_update, using, update_fields)
  File "/home/aruns/global/local/lib/python2.7/site-packages/django/db/models/base.py", line 846, in _save_table
    result = self._do_insert(cls._base_manager, using, fields, update_pk, raw)
  File "/home/aruns/global/local/lib/python2.7/site-packages/django/db/models/base.py", line 885, in _do_insert
    using=using, raw=raw)
  File "/home/aruns/global/local/lib/python2.7/site-packages/django/db/models/manager.py", line 127, in manager_method
    return getattr(self.get_queryset(), name)(*args, **kwargs)
  File "/home/aruns/global/local/lib/python2.7/site-packages/django/db/models/query.py", line 920, in _insert
    return query.get_compiler(using=using).execute_sql(return_id)
  File "/home/aruns/global/local/lib/python2.7/site-packages/django/db/models/sql/compiler.py", line 974, in execute_sql
    cursor.execute(sql, params)
  File "/home/aruns/global/local/lib/python2.7/site-packages/django/db/backends/utils.py", line 79, in execute
    return super(CursorDebugWrapper, self).execute(sql, params)
  File "/home/aruns/global/local/lib/python2.7/site-packages/django/db/backends/utils.py", line 64, in execute
    return self.cursor.execute(sql, params)
  File "/home/aruns/global/local/lib/python2.7/site-packages/django/db/utils.py", line 97, in __exit__
    six.reraise(dj_exc_type, dj_exc_value, traceback)
  File "/home/aruns/global/local/lib/python2.7/site-packages/django/db/backends/utils.py", line 64, in execute
    return self.cursor.execute(sql, params)
  File "/home/aruns/global/local/lib/python2.7/site-packages/django/db/backends/sqlite3/base.py", line 318, in execute
    return Database.Cursor.execute(self, query, params)
IntegrityError: UNIQUE constraint failed: auth_user.username
>>> u.set_password('indistylo#23')
Traceback (most recent call last):
  File "<console>", line 1, in <module>
NameError: name 'u' is not defined