lookup.py 文件源码

def get_template(self, uri):
        """Return a :class:`.Template` object corresponding to the given
        ``uri``.

        .. note:: The ``relativeto`` argument is not supported here at
           the moment.

        """

        try:
            if self.filesystem_checks:
                return self._check(uri, self._collection[uri])
            else:
                return self._collection[uri]
        except KeyError:
            u = re.sub(r'^\/+', '', uri)
            for dir in self.directories:
                # make sure the path seperators are posix - os.altsep is empty
                # on POSIX and cannot be used.
                dir = dir.replace(os.path.sep, posixpath.sep)
                srcfile = posixpath.normpath(posixpath.join(dir, u))
                if os.path.isfile(srcfile):
                    return self._load(srcfile, uri)
            else:
                raise exceptions.TopLevelLookupException(
                    "Cant locate template for uri %r" % uri)