def _get_index(self, server_url):
for i in range(len(self.sessions)):<EOL><INDENT>session = self.sessions[i]<EOL>if session.url == server_url:<EOL><INDENT>return i<EOL><DEDENT><DEDENT>return -<NUM_LIT:1><EOL>
Returns a registered GPServer object with a matching GenePattern server url
Returns -1 if no matching result was found
:param server_url:
:return: