old_contents: import pytest
  from lammps_data.uff_table import UffTable
  
  
  @pytest.fixture
  def uff_table():
      return UffTable()
  
  
  def test_lookup_of_nonexistent_element_should_raise_an_exception():
      pass
  
  
  def test_lookup_of_nonexistent_coordination_number_should_raise_an_exception():
      pass
  
  
  def test_lookup_of_matching_angle_should_return_the_row():
      pass
  
  
  def test_lookup_of_nonmatching_angle_should_return_the_row():
      pass
  
  
  def test_lookup_with_angle_multiplicity_using_low_tolerance_should_return_single_row():
      pass
  
  
  def test_lookup_with_angle_multiplicity_using_high_tolerance_should_raise_an_exception():
      pass
  
new_contents: import pytest
  from lammps_data.uff_table import UffTable, NonExistentElementError,
                                    NonExistentCoordinationError, NonExistentAngleError,
                                    LookupMultiplicityError
  
  
  @pytest.fixture
  def uff_table():
      return UffTable()
  
  
  def test_lookup_of_nonexistent_element_should_raise_an_exception(uff_table):
      with pytest.raises(NonExistentElementError):
          uff_table.lookup('M', 2, 180)
  
  
  def test_lookup_of_nonexistent_coordination_number_should_raise_an_exception(uff_table):
      with pytest.raises(NonExistentCoordinationError):
          uff_table.lookup('C', 5, 180)
  
  
  def test_lookup_of_nonexistent_angle_should_raise_an_exception(uff_table):
      with pytest.raises(NonExistentAngleError):
          uff_table.lookup('C', 4, 100, tolerance=0)
  
  
  def test_lookup_of_matching_angle_should_return_the_row(uff_table):
      expected_row = dict(type='C_1', bond=0.706, angle=180.0, distance=3.851, energy=0.105, scale=12.73, charge=1.912)
      assert uff_table.lookup('C', 2, 180, tolerance=0) == expected_row
  
  
  def test_lookup_of_angle_within_tolerance_should_return_the_row(uff_table):
      expected_row = dict(type='C_1', bond=0.706, angle=180.0, distance=3.851, energy=0.105, scale=12.73, charge=1.912)
      assert uff_table.lookup('C', 2, 175, tolerance=10) == expected_row
  
  
  def test_lookup_with_angle_multiplicity_using_low_tolerance_should_return_single_row():
      assert len(uff_table.lookup('O', 4, 104.51, tolerance=0)) == 1
  
  
  def test_lookup_with_angle_multiplicity_using_high_tolerance_should_raise_an_exception():
      with pytest.raises(LookupMultiplicityError):
          uff_table.lookup('O', 4, 104.51, tolerance=50)
  
subject: Add uff table tests and errors.