python 2.7 - Can't collectstatic to s3 in django using boto - s3 bucket returns a NoneType -

when want collectstatic s3 give typeerror

my settings.py

import os base_dir = os.path.dirname(os.path.dirname(__file__)) secret_key = 'something' #debug = false debug = true per_page    = 12  template_debug = true  allowed_hosts = ['xyz.com'] # application definition  installed_apps = (     'django.contrib.admin',     'django.contrib.auth',     'django.contrib.contenttypes',     'django.contrib.sessions',     'django.contrib.messages',     'django.contrib.staticfiles',     .....,     ......., ) if debug:      installed_apps = installed_apps + ('storages',)  middleware_classes = (     'django.contrib.sessions.middleware.sessionmiddleware',     'django.middleware.common.commonmiddleware',     'django.middleware.csrf.csrfviewmiddleware',     'django.contrib.auth.middleware.authenticationmiddleware',     'django.contrib.auth.middleware.sessionauthenticationmiddleware',     'django.contrib.messages.middleware.messagemiddleware',     'django.middleware.clickjacking.xframeoptionsmiddleware', )  template_context_processors = (     "django.contrib.auth.context_processors.auth",     "django.core.context_processors.debug",     "django.core.context_processors.i18n",     "django.core.context_processors.media",     "django.core.context_processors.static",     "django.core.context_processors.tz",     "django.contrib.messages.context_processors.messages", )   root_urlconf = 'myproject.urls'  if debug:     wsgi_application = 'myproject.wsgi_production.application' else:        wsgi_application = 'myproject.wsgi.application'   . import s3_custom # internationalization # https://docs.djangoproject.com/en/1.7/topics/i18n/  language_code = 'en-us'  time_zone = 'utc'  use_i18n = true  use_l10n = true  use_tz = true  aws_storage_bucket_name = 'bucket name' aws_access_key_id = 'key' aws_secret_access_key = 'access key' aws_s3_custom_domain ='https://bucketname.s3.amazonaws.com'  if debug:     staticfiles_dirs = ((os.path.join(base_dir,'mystatic')),)     #static_root = os.path.join(base_dir,'static')     #static_url = '/static/'     #media_root = (os.path.join(base_dir,'media'))     #media_url = aws_s3_custom_domain+'/media/'     template_dirs = (os.path.join(base_dir,'templates'),)      staticfiles_location = 'static'     staticfiles_storage = 'myproject.s3_custom.staticstorage'     static_url = aws_s3_custom_domain+'/'+staticfiles_location+'/'      mediafiles_location = 'media'     media_url = aws_s3_custom_domain+'/'+mediafiles_location+'/'     default_file_storage = 'myproject.s3_custom.mediastorage'      #default_file_storage = 'storages.backends.s3boto.s3botostorage'     #staticfiles_storage = 'storages.backends.s3boto.s3botostorage'      # databases      ....     ....... 

s3_custom.py

from storages.backends.s3boto import s3botostorage import os aws_storage_bucket_name = 'bucket name' aws_access_key_id = 'key' aws_secret_access_key = 'access key' aws_s3_custom_domain ='https://bucketname.s3.amazonaws.com'  class staticstorage(s3botostorage):     location = 'static'  class mediastorage(s3botostorage):     location = 'media' 

when run in terminal python manage.py collectstatic

error is

  file "manage.py", line 10, in <module>     execute_from_command_line(sys.argv)   file "/usr/local/lib/python2.7/dist-packages/django/core/management/__init__.py", line 385, in execute_from_command_line     utility.execute()   file "/usr/local/lib/python2.7/dist-packages/django/core/management/__init__.py", line 377, in execute     self.fetch_command(subcommand).run_from_argv(self.argv)   file "/usr/local/lib/python2.7/dist-packages/django/core/management/base.py", line 288, in run_from_argv     self.execute(*args, **options.__dict__)   file "/usr/local/lib/python2.7/dist-packages/django/core/management/base.py", line 338, in execute     output = self.handle(*args, **options)   file "/usr/local/lib/python2.7/dist-packages/django/core/management/base.py", line 533, in handle     return self.handle_noargs(**options)   file "/usr/local/lib/python2.7/dist-packages/django/contrib/staticfiles/management/commands/collectstatic.py", line 168, in handle_noargs     collected = self.collect()   file "/usr/local/lib/python2.7/dist  -packages/django/contrib/staticfiles/management/commands/collectstatic.py", line 107, in collect         handler(path, prefixed_path, storage)       file "/usr/local/lib/python2.7/dist-packages/django/contrib/staticfiles/management/commands/collectstatic.py", line 305, in copy_file         if not self.delete_file(path, prefixed_path, source_storage):       file "/usr/local/lib/python2.7/dist-packages/django/contrib/staticfiles/management/commands/collectstatic.py", line 218, in delete_file         if self.storage.exists(prefixed_path):       file "/usr/local/lib/python2.7/dist-packages/storages/backends/s3boto.py", line 414, in exists         return k.exists()       file "/usr/local/lib/python2.7/dist-packages/boto/s3/key.py", line 539, in exists         return bool(self.bucket.lookup(self.name, headers=headers))       file "/usr/local/lib/python2.7/dist-packages/boto/s3/bucket.py", line 142, in lookup         return self.get_key(key_name, headers=headers)       file "/usr/local/lib/python2.7/dist-packages/boto/s3/bucket.py", line 192, in get_key         key, resp = self._get_key_internal(key_name, headers, query_args_l)       file "/usr/local/lib/python2.7/dist-packages/boto/s3/bucket.py", line 199, in _get_key_internal         query_args=query_args)       file "/usr/local/lib/python2.7/dist-packages/boto/s3/connection.py", line 652, in make_request         auth_path = self.calling_format.build_auth_path(bucket, key)       file "/usr/local/lib/python2.7/dist-packages/boto/s3/connection.py", line 94, in build_auth_path         path = '/' + bucket     typeerror: cannot concatenate 'str' , 'nonetype' objects 

please me doing wrong give precious 4 hour cannot find error