Added clarifying commit to variable

geomagio/residual/SpreadsheetSummaryFactory.py

@@ -110,6 +110,7 @@ class SpreadsheetSummaryFactory(object):
         date = sheet["I1"].value
         base_date = f"{date.year}{date.month:02}{date.day:02}"
         readings = []
+        # define the number of sets in a spreadsheet:
         sets_len = len(
             [
                 sheet.cell(row=i, column=3).value
@@ -117,6 +118,7 @@ class SpreadsheetSummaryFactory(object):
                 if sheet.cell(row=i, column=3).value is not None
             ]
         )
+
         for d_n in range(10, 10 + sets_len):
             h_n = d_n + 14
             v_n = d_n + 28