def __getitem__(self, name):
        """Retrieves the description of a member with a given name.

        Returns
        -------
        :class:`Member`

        Raises
        ------
        :exc:`TypeError`
            If :py:`name` is not a string.
        :exc:`NameError`
            If :py:`name` is not a valid, public Python attribute name.
        :exc:`SignatureError`
            If a member called :py:`name` does not exist in the collection.
        """
        self._check_name(name)
        if name not in self._dict:
            raise SignatureError(f"Member '{name}' is not a part of the signature")
        return self._dict[name]
Retrieves the description of a member with a given name.

        Returns
        -------
        :class:`Member`

        Raises
        ------
        :exc:`TypeError`
            If :py:`name` is not a string.
        :exc:`NameError`
            If :py:`name` is not a valid, public Python attribute name.
        :exc:`SignatureError`
            If a member called :py:`name` does not exist in the collection.
        
amaranth/lib/wiring.py