code: def test_base_system():
      """Test BaseSystem. Checks that it doesn't raise errors."""
      from deepchem.utils.dft_utils import (
          BaseSystem,
          BaseHamilton,
          BaseGrid,
      )
  
      class MySystem(BaseSystem):
          def __init__(self):
              self.hamiltonian = BaseHamilton()
              self.grid = BaseGrid()
  
          def get_hamiltonian(self):
              return self.hamiltonian
  
          def get_grid(self):
              return self.grid
  
          def requires_grid(self):
              return True
  
      system = MySystem()
      assert system.requires_grid()
  
file_path: deepchem/deepchem/utils/test/test_dft_utils.py
imports: import pytest
  import numpy
  from typing import Union
label_desc: Use image node_id 16 for calling a global function with example usage: test_base_system() and returns: self, self, True