'Import a single module.'

def _import_one(self, parent, modname, fqname):

    try:
        return sys.modules[fqname]
    except KeyError:
        pass
    result = self.get_code(parent, modname, fqname)
    if (result is None):
        return
    else:
        module = self._process_result(result, fqname)
        if parent:
            setattr(parent, modname, module)
        return module
