def strindex_to_tuples(strindex):
        '''conviencience function for converting from a string index
        i.e. "A2:B20" into a tuple form ('A', 2), ('B', 20)'''
        start, end = strindex.split(':')
        i = first_index_lt(start, 'A')
        start = start[:i], int(start[i:])
        i = first_index_lt(end, 'A')
        end = end[:i], int(end[i:])
        return start, end
conviencience function for converting from a string index
        i.e. "A2:B20" into a tuple form ('A', 2), ('B', 20)
recipes/Python/578142_Working_with_Excel_Indexes/recipe-578142.py