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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 quota(ip=None):
 """Check your quota."""

    # TODO: Add arbitrary user defined IP check
    url = 'http://www.random.org/quota/?format=plain'
    data = urlopen(url)
    credit = int(data.read().strip())
    if data.code == 200:
        return credit
    else:
        return "ERROR: Server responded with code %s" % data.code