pydoc.py 文件源码

def showtopic(self, topic, more_xrefs=''):
        try:
            import pydoc_data.topics
        except ImportError:
            self.output.write('''
Sorry, topic and keyword documentation is not available because the
module "pydoc_data.topics" could not be found.
''')
            return
        target = self.topics.get(topic, self.keywords.get(topic))
        if not target:
            self.output.write('no documentation found for %s\n' % repr(topic))
            return
        if type(target) is type(''):
            return self.showtopic(target, more_xrefs)

        label, xrefs = target
        try:
            doc = pydoc_data.topics.topics[label]
        except KeyError:
            self.output.write('no documentation found for %s\n' % repr(topic))
            return
        pager(strip(doc) + '\n')
        if more_xrefs:
            xrefs = (xrefs or '') + ' ' + more_xrefs
        if xrefs:
            import StringIO, formatter
            buffer = StringIO.StringIO()
            formatter.DumbWriter(buffer).send_flowing_data(
                'Related help topics: ' + join(split(xrefs), ', ') + '\n')
            self.output.write('\n%s\n' % buffer.getvalue())