old_contents: import pytest
  from tardis.plasma.standard_plasmas import LegacyPlasmaArray
  
  @pytest.fixture
  def standard_legacy_plasma(t_rad, number_densities, time_explosion,
                                atomic_data, j_blues,
                                link_t_rad_t_electron):
      return LegacyPlasmaArray(number_densities, atomic_data, time_explosion,
                               t_rad)
subject: Remove unused fixture from test_complete_plasmas.