def __init__(self, source, target):
if source.locale != target.locale:<EOL><INDENT>raise ValueError(<EOL>'<STR_LIT>')<EOL><DEDENT>self.source = source<EOL>self.target = target<EOL>self.result = MessageCatalogue(source.locale)<EOL>self.domains = None<EOL>self.messages = {}<EOL>super(AbstractOperation, self).__init__()<EOL>
@type source: MessageCatalogue
@type target: MessageCatalogue
@raises ValueError