Gets the user name. The value can be stored in parameters "username" or "user".

        :return: the user name.

def get_username(self):
        """
        Gets the user name. The value can be stored in parameters "username" or "user".

        :return: the user name.
        """
        username = self.get_as_nullable_string("username")
        username = username if username != None else self.get_as_nullable_string("user")
        return username