code: def authenticate(self, email=None, password=None):
          
          if self.session.authenticate(email, password):
              return True
docs: Attempt to authenticate the user.
  
          Parameters
          ----------
          email : string
              The email of a user on Lending Club
          password : string
              The user's password, for authentication.
  
          Returns
          -------
          boolean
              True if the user authenticated or raises an exception if not
  
          Raises
          ------
          session.AuthenticationError
              If authentication failed
          session.NetworkError
              If a network error occurred