Returns the full url from path.

        If path is already a url, return it unchanged. If it's a path, append
        it to the stored url.

        Returns:
            str: The full URL

def _build_url(self, path):
        """Returns the full url from path.

        If path is already a url, return it unchanged. If it's a path, append
        it to the stored url.

        Returns:
            str: The full URL
        """
        if path.startswith('http://') or path.startswith('https://'):
            return path
        else:
            return '%s%s' % (self._url, path)