old_contents: """
  Classes for handling raster data.
  """
  
  import grid
  import aaigrid
  import raster
  import flow
  
  from grid import RegularGrid, StructuredGrid, aairead
  from aaigrid import AAIGrid
  from raster import witch_of_agnesi, peaks, pad, slope, aspect, grad, div
  from raster import normed_vector_field, fill_sinks
  
  try:
      from crfuncs import streamline2d
  except ImportError:
      from streamline import streamline2d
  
  try:
      import fill_sinks    # Cython
  except ImportError:
      print("Warning: experimental Cython fill_sinks not loaded")
  
  try:
      import flow          # Has a Scipy dependency
  except ImportError:
      print("Warning: raster.flow not loaded - perhaps scipy is missing")
  
  
new_contents: """
  Classes for handling raster data.
  """
  
  import grid
  import aaigrid
  import raster
  import flow
  
  from grid import RegularGrid, StructuredGrid, aairead
  from aaigrid import AAIGrid
  from raster import witch_of_agnesi, peaks, pad, slope, aspect, grad, div
  from raster import normed_vector_field
  
  try:
      from crfuncs import streamline2d
  except ImportError:
      from streamline import streamline2d
  
  try:
      import cfill_sinks as fill_sinks
  except ImportError:
      import fill_sinks
  
  try:
      import flow          # Has a Scipy dependency
  except ImportError:
      print("Warning: raster.flow not loaded")
  
  
subject: fix raster/__init__.py regression related to fill_sinks revamp