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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 prefixed_collapsible_map(m, prefix):
 """ Return a dict of params corresponding to those in m with the added prefix """

    if m == values.unset:
        return {}

    def flatten_dict(d, result={}, prv_keys=[]):
        for k, v in d.items():
            if isinstance(v, dict):
                flatten_dict(v, result, prv_keys + [k])
            else:
                result['.'.join(prv_keys + [k])] = v

        return result

    if isinstance(m, dict):
        flattened = flatten_dict(m)
        return {'{}.{}'.format(prefix, k): v for k, v in flattened.items()}

    return {}