First of all if you have 2 o2m relations with the same data you should re evaluate your data model. But filling o2m fields is done like in Hilar link, but this copy paste from the odoo documentation sux when you don't know what you're doing!

So if you you want so fill the model on the "many" side you need a dict of values that you just pass to the field that has the relation on the "one" side of the relation.

# field with the o2m relation
relation_ids = fields.One2Many()

# filling the many model
relation_ids = [(0, 0, dict_of_values)]

# OR
relation_ids = [(0, 0, {'field1': self.value1, 'field2': value2})]