'Deletes the specified policy document for the specified group.
:type group_name: string
:param group_name: The name of the group the policy is associated with.
:type policy_name: string
:param policy_name: The policy document to delete.'

def delete_group_policy(self, group_name, policy_name):

    params = {'GroupName': group_name, 'PolicyName': policy_name}
    return self.get_response('DeleteGroupPolicy', params, verb='POST')
