error in manage.py createsuperuser

/root/workspace/P1>./manage.py createsuperuser
Traceback (most recent call last):
  File "./manage.py", line 10, in <module>
    execute_from_command_line(sys.argv)
  File "/usr/lib/python2.7/site-packages/django/core/management/__init__.py", line 443, in execute_from_command_line
    utility.execute()
  File "/usr/lib/python2.7/site-packages/django/core/management/__init__.py", line 382, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/usr/lib/python2.7/site-packages/django/core/management/base.py", line 196, in run_from_argv
    self.execute(*args, **options.__dict__)
  File "/usr/lib/python2.7/site-packages/django/core/management/base.py", line 232, in execute
    output = self.handle(*args, **options)
  File "/usr/lib/python2.7/site-packages/django/contrib/auth/management/commands/createsuperuser.py", line 70, in handle
    default_username = get_default_username()
  File "/usr/lib/python2.7/site-packages/django/contrib/auth/management/__init__.py", line 105, in get_default_username
    default_username = get_system_username()
  File "/usr/lib/python2.7/site-packages/django/contrib/auth/management/__init__.py", line 85, in get_system_username
    return getpass.getuser().decode(locale.getdefaultlocale()[1])
TypeError: decode() argument 1 must be string, not None

To solve the above issues, type in

export LANG=en_US.UTF-8
export LC_ALL=en_US.UTF-8