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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 _reconstruct_relative_url(self, environ):
 """Reconstruct the relative URL of this request. This is based on the URL reconstruction code in Python PEP 333: http://www.python.org/dev/peps/pep-0333/#url-reconstruction. Rebuild the URL from the pieces available in the environment. Args: environ: An environ dict for the request as defined in PEP-333 Returns: The portion of the URL from the request after the server and port. """

    url = urllib.quote(environ.get('SCRIPT_NAME', ''))
    url += urllib.quote(environ.get('PATH_INFO', ''))
    if environ.get('QUERY_STRING'):
      url += '?' + environ['QUERY_STRING']
    return url