text: """
  Compute the dielectric matrix and its inverse.
  
  Depends on:
      12-Wfn
      13-Wfnq
  
  Used by:
      22-Sigma
      23-Kernel
      24-Absorption
  """
  from BGWpy import Structure, EpsilonTask
  
  task = EpsilonTask(
      dirname='21-Epsilon',
      structure = Structure.from_file('../../Data/Structures/GaAs.json'),
  
      ngkpt = [2,2,2],        # k-points grid
      qshift = [.001,.0,.0],  # q-shift to treat the Gamma point
      ecuteps = 10.0,         # Energy cutoff for the epsilon matrix
  
      # Files to be linked
      wfn_fname='12-Wfn/wfn.cplx',
      wfnq_fname='13-Wfnq/wfn.cplx',
  
      # Parameters for the MPI runner
      nproc = 2,
      nproc_per_node = 2,
      mpirun = 'mpirun',
      nproc_flag = '-n',
      nproc_per_node_flag = '--npernode',
      )
  
  
  # Execution
  task.write()
  task.run()
  task.report()
  
  