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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 filter_params(params):
 """ convert dict value if value is bool type, False -> "false" True -> "true" """

    if params is not None:
        new_params = copy.deepcopy(params)
        new_params = dict((k, v) for k, v in new_params.items() if v is not None)
        for key, value in new_params.items():
            if isinstance(value, bool):
                new_params[key] = "true" if value else "false"
        return new_params