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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 requires_conversion(cls, fileset, file_format):
 """Checks whether the fileset matches the requested file format"""

        if file_format is None:
            return False
        try:
            filset_format = fileset.format
        except AttributeError:
            return False  # Field input
        else:
            return (file_format != filset_format)