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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_broken_link(url):
 """Determine whether the link returns a 404 error."""

    try:
        request = urllib_request.Request(
            url, headers={'User-Agent': 'Mozilla/5.0'})
        urllib_request.urlopen(request).read()
        return False
    except urllib_request.URLError:
        return True
    except SocketError:
        return True