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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 copy(self, *, continuations: List[memoryview] = None, expected: Sequence[Type['Parseable']] = None, list_expected: Sequence[Type['Parseable']] = None, command_name: bytes = None, uid: bool = None, charset: str = None, tag: bytes = None, max_append_len: int = None, allow_continuations: bool = None) -> 'Params': """Copy the parameters, possibly replacing a subset."""

        kwargs: Dict[str, Any] = {}
        self._set_if_none(kwargs, 'continuations', continuations)
        self._set_if_none(kwargs, 'expected', expected)
        self._set_if_none(kwargs, 'list_expected', list_expected)
        self._set_if_none(kwargs, 'command_name', command_name)
        self._set_if_none(kwargs, 'uid', uid)
        self._set_if_none(kwargs, 'charset', charset)
        self._set_if_none(kwargs, 'tag', tag)
        self._set_if_none(kwargs, 'max_append_len', max_append_len)
        self._set_if_none(kwargs, 'allow_continuations', allow_continuations)
        return Params(**kwargs)