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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 lookup_reverse(ip_address):
 """Perform a reverse lookup of IP address."""

    try:
        type(ipaddress.ip_address(ip_address))
    except ValueError:
        return {}

    record = reversename.from_address(ip_address)
    hostname = str(resolver.query(record, "PTR")[0])[:-1]
    return {'hostname': hostname}