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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 _serialize_inputs(inputs):
 """Serialize task input dictionary"""

        serialized_inputs = {}
        for input_id, input_value in inputs.items():
            if isinstance(input_value, list):
                serialized_list = Task._serialize_input_list(input_value)
                serialized_inputs[input_id] = serialized_list
            else:
                if isinstance(input_value, File):
                    input_value = Task._to_api_file_format(input_value)
                serialized_inputs[input_id] = input_value
        return serialized_inputs