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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_stream_kwargs(stream, kwargs, reverse=False):
 """ Given a stream and a kwargs dictionary of parameter values, map to the corresponding dictionary where the keys are substituted with the appropriately renamed string. If reverse, the output will be a dictionary using the original parameter names given a dictionary using the renamed equivalents. """

    mapped_kwargs = {}
    mapping = stream_name_mapping(stream, reverse=reverse)
    for k,v in kwargs.items():
        if k not in mapping:
            msg = 'Could not map key {key} {direction} renamed equivalent'
            direction = 'from' if reverse else 'to'
            raise KeyError(msg.format(key=repr(k), direction=direction))
        mapped_kwargs[mapping[k]] = v
    return mapped_kwargs