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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 connection_ok():
 """Check web connection. Returns True if web connection is OK, False otherwise. """

    try:
        urlopen(Dataset.base_url, timeout=1)
        # if an index page is ever added, this will pass through
        return True
    except HTTPError:
        # There's no index for BASE_URL so Error 404 is expected
        return True
    except URLError:
        # This is raised if there is no internet connection
        return False