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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 _ExtractGoogleDocsSearchQuery(self, url):
 """Extracts a search query from a Google docs URL. Google Docs: https://docs.google.com/.*/u/0/?q=query Args: url (str):
 URL. Returns: str: search query or None if no query was found. """

    if 'q=' not in url:
      return None

    line = self._GetBetweenQEqualsAndAmpersand(url)
    if not line:
      return None

    return line.replace('+', ' ')