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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 pad_chunk_columns(chunk):
 """Given a set of items to be inserted, make sure they all have the same columns by padding columns with None if they are missing."""

    columns = set()
    for record in chunk:
        columns.update(record.keys())
    for record in chunk:
        for column in columns:
            record.setdefault(column, None)
    return chunk