'Adds or updates the specified policy document for the specified user.
:type user_name: string
:param user_name: The name of the user the policy is associated with.
:type policy_name: string
:param policy_name: The policy document to get.
:type policy_json: string
:param policy_json: The policy document.'

def put_user_policy(self, user_name, policy_name, policy_json):

    params = {'UserName': user_name, 'PolicyName': policy_name, 'PolicyDocument': policy_json}
    return self.get_response('PutUserPolicy', params, verb='POST')
