#!/usr/bin/env python
# tries stress SST, SAT and MSAT
from  openpyxl import *
wb = load_workbook(filename='VAS-1.xlsx', read_only=True)    # open work book for processing
ws = wb['list2']    # use this worksheet
cell=0
def count_cells_with_data(row):
    if row is None:
        print('Argument is None')
    elif type(row) is not str:
        print('Error: '+str(row)+' this value is not string')
    else:
        i = 1
        data = 0
        result=row+str(i)
        while True:
            if ws[result].value is None:
                print('end')
            else: #ws[result].value is not None:
                data = data + 1
                i = i + 1
                result = row + str(i)
                # print(ws[result].value)
        print(data)
        print('end')
count_cells_with_data('A')

 Traceback (most recent call last):
  File "/Users/alexeylaptev/PycharmProjects/exelPython/main.py", line 33, in <module>
    count_cells_with_data('A')
  File "/Users/alexeylaptev/PycharmProjects/exelPython/main.py", line 21, in count_cells_with_data
    if ws[result].value is None:
  File "/usr/local/lib/python2.7/site-packages/openpyxl/worksheet/read_only.py", line 83, in __getitem__
    return meth(key)
  File "/usr/local/lib/python2.7/site-packages/openpyxl/worksheet/worksheet.py", line 371, in __getitem__
    return self._get_cell(min_row, min_col)
  File "/usr/local/lib/python2.7/site-packages/openpyxl/worksheet/read_only.py", line 182, in _get_cell
    cell = tuple(self.get_squared_range(column, row, column, row))[0]
IndexError: tuple index out of range
Process finished with exit code 1

 while True: