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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 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)