old_contents: """
  These classes provide the most basic structures required by
  the Image class.
  """
  
  from neuroimaging.core.reference.grid import SamplingGrid
  
  class BaseImage(object):
      """
      This class define a minimal interface which different types of images
      should implement. This interface is used by the Image class, which is
      the class which should be used by applications.
      """
  
      def __init__(self, data, grid, sctype):
          self.grid = grid
          self.data = data
          self.sctype = sctype
          
      def __getitem__(self, item):
          return self.data[item]
          
      def __setitem__(self, item, value):
          self.data[item] = value
  
  class ArrayImage (BaseImage):
      """A simple class to mimic an image file from an array."""
      def __init__(self, data, grid=None):
          """
          Create an ArrayImage instance from an array,
          by default assumed to be 3d.
  
          >>> from numpy import *
          >>> from neuroimaging.core.image.image import Image
          >>> z = Image.ArrayImage(zeros((10,20,20)))
          >>> print z.ndim
          3
          """
          grid = grid and grid or SamplingGrid.identity(data.shape)
          sctype = data.dtype.type
          BaseImage.__init__(self, data, grid, sctype)
  
  
new_contents: """
  These classes provide the most basic structures required by
  the Image class.
  """
  
  from neuroimaging.core.reference.grid import SamplingGrid
  
  class BaseImage(object):
      """
      This class defines a minimal interface which different types of images
      should implement. This interface is used by the Image class, which is
      the class which should be used by applications.
      """
  
      def __init__(self, data, grid, sctype):
          self.grid = grid
          self.data = data
          self.sctype = sctype
          
      def __getitem__(self, item):
          return self.data[item]
          
      def __setitem__(self, item, value):
          self.data[item] = value
  
  class ArrayImage (BaseImage):
      """A simple class to mimic an image file from an array."""
      def __init__(self, data, grid=None):
          """
          Create an ArrayImage instance from an array,
          by default assumed to be 3d.
  
          >>> from numpy import *
          >>> from neuroimaging.core.image.image import Image
          >>> z = Image.ArrayImage(zeros((10,20,20)))
          >>> print z.ndim
          3
          """
          grid = grid and grid or SamplingGrid.identity(data.shape)
          sctype = data.dtype.type
          BaseImage.__init__(self, data, grid, sctype)
  
  
subject: fix docstring typo