code: def set_application_name(self, options):
          
          supported_backends = ['django.db.backends.postgresql',
                                'django.db.backends.postgresql_psycopg2']
          opt_name = 'fallback_application_name'
          default_app_name = 'django_shell'
          app_name = default_app_name
          dbs = getattr(settings, 'DATABASES', [])
  
          # lookup over all the databases entry
          for db in dbs.keys():
              if dbs[db]['ENGINE'] in supported_backends:
                  try:
                      options = dbs[db]['OPTIONS']
                  except KeyError:
                      options = {}
  
                  # dot not override a defined value
                  if opt_name in options.keys():
                      app_name = dbs[db]['OPTIONS'][opt_name]
                  else:
                      dbs[db].setdefault('OPTIONS', {}).update({opt_name: default_app_name})
                      app_name = default_app_name
  
          return app_name
docs: Set the application_name on PostgreSQL connection
  
          Use the fallback_application_name to let the user override
          it with PGAPPNAME env variable
  
          http://www.postgresql.org/docs/9.4/static/libpq-connect.html#LIBPQ-PARAMKEYWORDS  # noqa