Remove a user from a group

        :type user: str
        :param user: User's email

        :type group: str
        :param group: Group name

        :rtype: dict
        :return: an empty dictionary

def remove_from_group(self, group, user):
        """
        Remove a user from a group

        :type user: str
        :param user: User's email

        :type group: str
        :param group: Group name

        :rtype: dict
        :return: an empty dictionary
        """
        data = {'group': group, 'user': user}
        return self.post('removeUserFromGroup', data)