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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 move_back(columns=1, file=sys.stdout):
 """ Move the cursor back a number of columns. Esc[<columns>D: Moves the cursor back by the specified number of columns without changing lines. If the cursor is already in the leftmost column, ANSI.SYS ignores this sequence. """

    move.back(columns).write(file=file)