old_contents: """Optional interoperability with Numpy."""
  
  import numpy
  
  NUMPY_DTYPES = {'ibm': numpy.dtype('f4'),
                  'l':   numpy.dtype('i4'),
                  'h':   numpy.dtype('i2'),
                  'f':   numpy.dtype('f4'),
                  'b':   numpy.dtype('i1')}
  
  
  def make_dtype(data_sample_format):
      """Convert a SEG Y data sample format to a compatible numpy dtype.
  
      Note :
          IBM float data sample formats ('ibm') will correspond to IEEE float data types.
  
      Args:
          data_sample_format: A data sample format string.
  
      Returns:
          A numpy.dtype instance.
  
      Raises:
          ValueError: For unrecognised data sample format strings.
      """
      try:
          return NUMPY_DTYPES[data_sample_format]
      except KeyError:
          raise ValueError("Unknown data sample format string {!r}".format(data_sample_format))
  
  
  
new_contents: """Optional interoperability with Numpy."""
  
  import numpy
  
  NUMPY_DTYPES = {'ibm':     numpy.dtype('f4'),
                  'int32':   numpy.dtype('i4'),
                  'int16':   numpy.dtype('i2'),
                  'float32': numpy.dtype('f4'),
                  'int8':    numpy.dtype('i1')}
  
  
  def make_dtype(data_sample_format):
      """Convert a SEG Y data sample format to a compatible numpy dtype.
  
      Note :
          IBM float data sample formats ('ibm') will correspond to IEEE float data types.
  
      Args:
          data_sample_format: A data sample format string.
  
      Returns:
          A numpy.dtype instance.
  
      Raises:
          ValueError: For unrecognised data sample format strings.
      """
      try:
          return NUMPY_DTYPES[data_sample_format]
      except KeyError:
          raise ValueError("Unknown data sample format string {!r}".format(data_sample_format))
  
  
  
subject: Update numpy dtypes extension for correct type codes.