Openpyxl update Data Validation - openpyxl

Question

I want to create a drop down list in a excel sheet, and be able to update it when I load this sheet. When I change the items in my DataValidation list, and add it to the sheet, the list doesn't change.
Is there a way to update my list or just delete it?
wb = openpyxl.load_workbook(path)
ws_meteo = wb.active
dv = DataValidation(type="list", formula1=Formule, allow_blank=True)
dv.add_cell(ws_meteo['A10'])
ws_meteo.add_data_validation(dv)
wb.save(path)

Answer 1

Being five years late. I think I've encountered the same issue you did.
I have a excel file which needs unique data validation list for individual cells based on an external web service. This works fine when there is no data validation present in the cell. However if a data validation list is present, it appends another data validation list to the cell. On opening the file in Excel, It appears to select the first data validation list it encounters, thus the dropdown list never changes.
I solved it by removing any existing data validation for that cell before adding the new one. I used the following code.
def removeExistingCellDataValidation(worksheet, cell):
toRemove = []
# Append all validation rules for cell to be removed.
for validation in worksheet.data_validations.dataValidation:
if validation.__contains__(cell):
toRemove.append(validation)
# Process all data validation rules set for removal.
for rmValidation in toRemove:
worksheet.data_validations.dataValidation.remove(rmValidation)
After clearing the existing data validation I add the new data validation list as usual, the same way you do in your code snippet.