'This operation returns the operation IDs of operations that
are not yet complete.
:type marker: string
:param marker: For an initial request for a list of operations, omit
this element. If the number of operations that are not yet complete
is greater than the value that you specified for `MaxItems`, you
can use `Marker` to return additional operations. Get the value of
`NextPageMarker` from the previous response, and submit another
request that includes the value of `NextPageMarker` in the `Marker`
element.
Type: String
Default: None
Required: No
:type max_items: integer
:param max_items: Number of domains to be returned.
Type: Integer
Default: 20
Constraints: A value between 1 and 100.
Required: No'

def list_operations(self, marker=None, max_items=None):

    params = {}
    if (marker is not None):
        params['Marker'] = marker
    if (max_items is not None):
        params['MaxItems'] = max_items
    return self.make_request(action='ListOperations', body=json.dumps(params))
