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ipaddress: subnet_of() and supernet_of() raise confusing TypeError wrapping an AttributeError when passed an Address object #153769

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@Builder106

Bug report

Bug description:

When calling subnet_of() or supernet_of() on an IPv4Network or IPv6Network and passing an address object (e.g., IPv6Address) instead of a network object, the module attempts to access the network_address attribute on the address object. This raises an AttributeError, which is then caught by the broader exception handling in _is_subnet_of, resulting in a confusing TypeError that completely masks the original attribute access failure.

The method should explicitly check that the other argument is a network object (or at least raise a clear TypeError stating that a network object is required) rather than failing internally with an AttributeError that gets swallowed into a generic containment error.

Repro:

import ipaddress
ipaddress.IPv6Network('::/0').subnet_of(ipaddress.IPv6Address('::1'))

Traceback:

AttributeError: 'IPv6Address' object has no attribute 'network_address'

During handling of the above exception, another exception occurred:

TypeError: Unable to test subnet containment between ::/0 and ::1

ipaddress_repro.py

CPython versions tested on:

3.14

Operating systems tested on:

macOS

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    stdlibStandard Library Python modules in the Lib/ directorytype-bugAn unexpected behavior, bug, or error

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