Typing error in ContactList column type

[APCBoston]

When I use smartsheet.Sheets.get_column() to retrieve a column whose type is CONTACT_LIST, the returned JSON payload improperly reflects a column type TEXT_NUMBER. If I then call update_column() to update the contact list, the API returns an error:

"errorCode": 1090, "message": "Column.type is required when changing symbol, systemColumnType, options, contactOptions, or autoNumberFormat.", "refId": "h3w1i3"

All well and good, but if I then call update_column() with type set to CONTACT_LIST, I get a different error:

{"result": {"code": 1087, "errorCode": 1087, "message": "The column specified is used in a conditional formatting rule, so the column cannot be deleted and its type cannot be changed.", "name": "ApiError", "recommendation": "Do not retry without fixing the problem. ", "refId": "vuhctf", "shouldRetry": false, "statusCode": 400}}

Of course, I don't WANT to delete the column or change its type -- the type should already be CONTACT_LIST. When looking at the column properties in the web app, the type is correct: CONTACT_LIST. But for some reason the API thinks it is a TEXT_NUMBER and thus makes it impossible to update the contact list options!

[TarekSalha]

I got into the very same problem as you did. Although, the issue is quite old, I want to post the solution to the problem:
the types CONTACT_LIST and MULTI_CONTACT_LIST are not retrieved due to the api being backwards compatible (see here).

you can change the compatibility level via retrieving the object_level field as well as setting the api level to 2

_client.Sheets.get_sheet(sheet_id=id, include=["columnType", "objectValue"], level=2)

be careful, the structure of the column will vary depending on the column types of your sheet. For writing back the value, you could do the following:

new_cell = smartsheet.models.Cell()
new_cell.column_id = column_mapper[update.column_name]
if update.column_type  == "MULTI_CONTACT_LIST":
    if update.value:
        new_cell.object_value = smartsheet.models.MultiContactObjectValue()
        new_cell.object_value.values = [smartsheet.models.ContactObjectValue(props={"email": mail.strip()}) for mail in update.value.split(",")] # assuming update.value to be of form "chuck@norris.com, someUser@test.com,..."
    else:
        new_cell.value = smartsheet.models.ExplicitNull()

hope this helps everyone stepping into the same problem :-)

[APCBoston]

@TarekSalha thanks so much for posting your solution!