You need to open the file as rb mode
b = bynary file
r = only read the file
f = open('//X/str/Db/C/Source/selection/Date/Test/12.xlsx', 'rb')
You can use pandas library that will do most of the work for you
import pandas
import pandas
f = pandas.read_excel(open('//X/str/Db/C/Source/selection/Date/Test/12.xlsx','rb'), sheetname='Sheet 1')
# or using sheet index starting 0
f = pandas.read_excel(open('//X/str/Db/C/Source/selection/Date/Test/12.xlsx','rb'), sheetname=2)
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