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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 debug_bad_encoding(data):
 """Let's try to help user figure out what is at fault."""

        at_fault_files = set()
        for source_file_data in data['source_files']:
            for value in source_file_data.values():
                try:
                    json.dumps(value)
                except UnicodeDecodeError:
                    at_fault_files.add(source_file_data['name'])

        if at_fault_files:
            log.error('HINT: Following files cannot be decoded properly into '
                      'unicode. Check their content: %s',
                      ', '.join(at_fault_files))