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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 set_html(self, html, url = None):
 """ Sets custom HTML in our Webkit session and allows to specify a fake URL. Scripts and CSS is dynamically fetched as if the HTML had been loaded from the given URL. """

    if url:
      self.conn.issue_command('SetHtml', html, url)
    else:
      self.conn.issue_command('SetHtml', html)