load_workbook error in 3.0.5 not in 3.0.4
The attached file cannot be opened by openpyxl 3.0.5, while it works for version 3.0.4 ``import openpyxl as oxl`` ``oxl.load_workbook('openpyxl.xlsx')`` ``` /lib/python3.7/site-packages/openpyxl/descriptors/sequence.py in __set__(self, instance, seq) 23 def __set__(self, instance, seq): 24 if not isinstance(seq, self.seq_types): ---> 25 raise TypeError("Value must be a sequence") 26 seq = [_convert(self.expected_type, value) for value in seq] 27 if self.unique: TypeError: Value must be a sequence ``` [openpyxl.xlsx](/uploads/4cfba9463b905b7a107b92f97bd20a68/openpyxl.xlsx)
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