ListUsableSubnetworksRequest requests the list of usable
subnetworks available to a user for creating clusters.
The parent project where subnetworks are usable. Specified
in the format projects/*.
Filtering currently only supports equality on the
networkProjectId and must be in the form:
"networkProjectId=[PROJECTID]", where networkProjectId
is the project which owns the listed subnetworks. This
defaults to the parent project ID.
The max number of results per page that should be returned.
If the number of available results is larger than
page_size, a next_page_token is returned which can
be used to get the next page of results in subsequent
requests. Acceptable values are 0 to 500, inclusive.
Specifies a page token to use. Set this to
the nextPageToken returned by previous list
requests to get the next page of results.