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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 opengraph_get(html, prop):
 """ Extract specified OpenGraph property from html. 'http://example.com/img.jpg' 'http://example.com/img2.jpg' 'http://example.com/img3.jpg' """

    match = re.search('<meta [^>]*property="og:' + prop + '" content="([^"]*)"', html)
    if match is None:
        match = re.search('<meta [^>]*content="([^"]*)" property="og:' + prop + '"', html)
        if match is None:
            return None
    return match.group(1)