'Test Worksheet _calculate_spans()'

def test_calculate_spans_2(self):

    row = 1
    col = 0
    for i in range(row, (row + 17)):
        self.worksheet.write_number(i, col, 1)
        col = (col + 1)
    self.worksheet._calculate_spans()
    got = self.worksheet.row_spans
    exp = {0: '1:15', 1: '16:17'}
    self.assertEqual(got, exp)
