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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 prefix_dict_keys(d: Dict[str, Any], prefix: str) -> Dict[str, Any]: """ Returns a dictionary that's a copy of as ``d`` but with ``prefix`` prepended to its keys. """

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