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('+', ' ')