Cannot add multiple sort conditions
I'm trying to add multiple sort conditions to a worksheet. The file is correctly saved but an error is displayed by Excel while opening it. Example: ```python from random import randrange from openpyxl import Workbook wb = Workbook() ws = wb.active data = [ ["Fruit", "Quantity", "Price"], ["Kiwi", randrange(0, 10, 1), randrange(1, 100, 1)], ["Grape", randrange(0, 10, 1), randrange(1, 100, 1)], ["Apple", randrange(0, 10, 1), randrange(1, 100, 1)], ["Peach", randrange(0, 10, 1), randrange(1, 100, 1)], ["Pomegranate", randrange(0, 10, 1), randrange(1, 100, 1)], ["Pear", randrange(0, 10, 1), randrange(1, 100, 1)], ["Tangerine", randrange(0, 10, 1), randrange(1, 100, 1)], ["Blueberry", randrange(0, 10, 1), randrange(1, 100, 1)], ["Mango", randrange(0, 10, 1), randrange(1, 100, 1)], ["Watermelon", randrange(0, 10, 1), randrange(1, 100, 1)], ["Blackberry", randrange(0, 10, 1), randrange(1, 100, 1)], ["Orange", randrange(0, 10, 1), randrange(1, 100, 1)], ["Raspberry", randrange(0, 10, 1), randrange(1, 100, 1)], ["Banana", randrange(0, 10, 1), randrange(1, 100, 1)] ] for r in data: ws.append(r) ws.auto_filter.ref = "A1:C15" ws.auto_filter.add_sort_condition("B2:B15", descending=True) ws.auto_filter.add_sort_condition("C2:C15") wb.save("filtered.xlsx") ```
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