Gets new credentials

        :return: User credentials created via OAuth

def get_user_credentials(self):
        """Gets new credentials

        :return: User credentials created via OAuth
        """
        # create path to user credentials if needed
        if not os.path.exists(os.path.dirname(self.user_credentials)):
            os.makedirs(os.path.dirname(self.user_credentials))

        credentials = self.store.get()  # retrieve credentials
        needs_to_be_updated = not credentials or credentials.invalid
        if needs_to_be_updated:
            self.get_new_user_credentials()  # get new user credentials
            credentials = self.store.get()  # retrieve new credentials

        return credentials