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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 _iter_files(self, mod_name):
        '''
        Iterate over all file_mapping files in order of closeness to mod_name
        '''
        # do we have an exact match?
        if mod_name in self.file_mapping:
            yield mod_name

        # do we have a partial match?
        for k in self.file_mapping:
            if mod_name in k:
                yield k

        # anyone else? Bueller?
        for k in self.file_mapping:
            if mod_name not in k:
                yield k