def has(self, id, domain):
assert isinstance(id, (str, unicode))<EOL>assert isinstance(domain, (str, unicode))<EOL>if self.defines(id, domain):<EOL><INDENT>return True<EOL><DEDENT>if self.fallback_catalogue is not None:<EOL><INDENT>return self.fallback_catalogue.has(id, domain)<EOL><DEDENT>return False<EOL>
Checks if a message has a translation.

@rtype: bool
@return: true if the message has a translation, false otherwise