old_contents: import numpy
  
  if numpy.__name__ == "bohrium":
      warnings.warn(
          "Running veros with 'python -m bohrium' is discouraged (use '--backend bohrium' instead)")
      import numpy_force
      numpy = numpy_force
  
  try:
      import bohrium
      import bohrium.lapack
  except ImportError:
      warnings.warn("Could not import Bohrium")
      bohrium = None
  
  BACKENDS = {"numpy": numpy, "bohrium": bohrium}
  
  
  def get_backend(backend):
      if backend not in BACKENDS.keys():
          raise ValueError("unrecognized backend {} (must be either of: {!r})"
                           .format(backend, BACKENDS.keys()))
      if BACKENDS[backend] is None:
          raise ValueError("{} backend failed to import".format(backend))
      return BACKENDS[backend], backend
  
new_contents: import numpy
  import warnings
  
  if numpy.__name__ == "bohrium":
      warnings.warn("Running veros with 'python -m bohrium' is discouraged (use '--backend bohrium' instead)")
      import numpy_force
      numpy = numpy_force
  
  try:
      import bohrium
      import bohrium.lapack
  except ImportError:
      warnings.warn("Could not import Bohrium")
      bohrium = None
  
  BACKENDS = {"numpy": numpy, "bohrium": bohrium}
  
  
  def get_backend(backend):
      if backend not in BACKENDS.keys():
          raise ValueError("unrecognized backend {} (must be either of: {!r})"
                           .format(backend, BACKENDS.keys()))
      if BACKENDS[backend] is None:
          raise ValueError("{} backend failed to import".format(backend))
      return BACKENDS[backend], backend
  
subject: add missing import