'Create an instance of OAuth2Credentials
This is one of the few types if Credentials that you should contrust,
Credentials objects are usually instantiated by a Flow.
Args:
access_token: string, access token.
user_agent: string, The HTTP User-Agent to provide for this application.
Notes:
store: callable, a callable that when passed a Credential
will store the credential back to where it came from.'

def __init__(self, access_token, user_agent):

    super(AccessTokenCredentials, self).__init__(access_token, None, None, None, None, None, user_agent)
