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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 find_needed_input(input_format):
 """ Find a needed input class input_format - needed input format, see utils.input.dataformats """

    needed_inputs = [re.cls for re in registry if re.category==RegistryCategories.inputs and re.cls.input_format == input_format]
    if len(needed_inputs)>0:
        return needed_inputs[0]
    return None