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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 rename_keys(d: Dict[str, Any], mapping: Dict[str, str]) -> Dict[str, Any]: """ Returns a copy of the dictionary ``d`` with its keys renamed according to ``mapping``. Args: d: the starting dictionary mapping: a dictionary of the format ``{old_key_name: new_key_name}`` Returns: a new dictionary Keys that are not in ``mapping`` are left unchanged. The input parameters are not modified. """

    result = {}  # type: Dict[str, Any]
    for k, v in d.items():
        if k in mapping:
            k = mapping[k]
        result[k] = v
    return result