The backend has a column limit of 152. The current procedure is creating a ColumnModel for each column and then assigning them to the schema. When the number of columns exceeds 152, the user must wait a very long time before the user is given the error that the max column limit is 152. We should just check the len() of the list of columns before even creating any new ones to make sure it does not exceed the limit.
Works for me.
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