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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 _ExtractYahooSearchQuery(self, url):
 """Extracts a search query from a Yahoo search URL. Examples: https://search.yahoo.com/search?p=query https://search.yahoo.com/search;?p=query Args: url (str):
 URL. Returns: str: search query or None if no query was found. """

    if 'p=' not in url:
      return None
    _, _, line = url.partition('p=')
    before_and, _, _ = line.partition('&')
    if not before_and:
      return None
    yahoo_search_url = before_and.split()[0]

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