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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 mapping_of(cls):
 """Expects a mapping from some key to data for `cls` instances."""

    def mapper(data):
        if not isinstance(data, Mapping):
            raise TypeError(
                "data must be a mapping, not %s"
                % type(data).__name__)
        return {
            key: cls(value)
            for key, value in data.items()
        }
    return mapper