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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_ip(address):
 """ Returns True if address is a valid IP address. """

    try:
        # Test to see if already an IPv4/IPv6 address
        address = netaddr.IPAddress(address)
        return True
    except (netaddr.AddrFormatError, ValueError):
        return False