I am checking data output in some testing code, and only some fields can be None, but I think this can be better:
for key in data[0].keys():
self.assertIn(key, data_model)
if data[0][key] is None:
self.assertTrue('rate' in key or 'percentage' in key or 'ratio' in key)
continue
self.assertIsInstance(data[0][key], data_model[key])
Mostly I don't like the ... or ... in the assertTrue