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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def GroupsUsersDelete(self, group_id, user_id):

 """
 Delete a user from a group in CommonSense.
 
 @return (bool) - Boolean indicating whether GroupsPost was successful.
 """

        if self.__SenseApiCall__('/groups/{group_id}/users/{user_id}.json'.format(group_id = group_id, user_id = user_id), 'DELETE'):
            return True
        else:
            self.__error__ = "api call unsuccessful"
            return False