def list_communities(self, token=None):
parameters = dict()<EOL>if token:<EOL><INDENT>parameters['<STR_LIT>'] = token<EOL><DEDENT>response = self.request('<STR_LIT>', parameters)<EOL>return response<EOL>
List all communities visible to a user.

:param token: (optional) A valid token for the user in question.
:type token: None | string
:returns: The list of communities.
:rtype: list[dict]