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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 is_svn_page(html):
 # type: (Union[str, Text]) -> Optional[Match[Union[str, Text]]] """ Returns true if the page appears to be the index page of an svn repository """

    return (re.search(r'<title>[^<]*Revision \d+:', html) and
            re.search(r'Powered by (?:<a[^>]*?>)?Subversion', html, re.I))