Delete a tag or populator by value - these are processed before upserts

def add_delete(self, value):
        """Delete a tag or populator by value - these are processed before upserts"""

        value = value.strip()
        v = value.lower()
        self.lower_val_to_val[v] = value
        if len(v) == 0:
            raise ValueError("Invalid value for delete. Value is empty.")

        self.deletes.add(v)