code: def test_get_invalid(self):
      with self.assertRaises(IndexError):
          self.row[3]
  
      with self.assertRaises(KeyError):
          self.row["foo"]
  
imports: import unittest
  from agate.mapped_sequence import MappedSequence
label_desc: Use image node_id 13 for calling the TestMappedSequence obj's underlying member method code with example usage: obj.test_get_invalid() without return types