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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 column(environment, book, sheet_name, sheet_source, column_source, column_key):
 """ Returns an array of values from column from a different dataset, ordered as the key. """

    a = book.sheets[sheet_source]
    b = book.sheets[sheet_name]

    return environment.copy([a.get(**{column_key: row[column_key]})[column_source] for row in b.all()])