old_contents: from __future__ import (absolute_import, division, print_function,
                          unicode_literals)
  
  import numpy as np
  
  from astropy.tests.helper import pytest
  from astropy import units as u
  from astropy.utils import NumpyRNGContext
  
  from ..ccddata import CCDData
  
  # If additional pytest markers are defined the key in the dictionary below
  # should be the name of the marker.
  DEFAULTS = {
      'seed': 123,
      'data_size': 100,
      'data_scale': 1.0,
      'data_mean': 0.0
  }
  
  DEFAULT_SEED = 123
  DEFAULT_DATA_SIZE = 100
  DEFAULT_DATA_SCALE = 1.0
  
  
  def value_from_markers(key, request):
      try:
          val = request.keywords[key].args[0]
      except KeyError:
          val = DEFAULTS[key]
      return val
  
  
  @pytest.fixture
  def ccd_data(request):
      """
      Return a CCDData object with units of ADU.
  
      The size of the data array is 100x100 but can be changed using the marker
      @pytest.mark.data_size(N) on the test function, where N should be the
      desired dimension.
  
      Data values are initialized to random numbers drawn from a normal
      distribution with mean of 0 and scale 1.
  
      The scale can be changed with the marker @pytest.marker.scale(s) on the
      test function, where s is the desired scale.
  
      The mean can be changed with the marker @pytest.marker.scale(m) on the
      test function, where m is the desired mean.
      """
      size = value_from_markers('data_size', request)
      scale = value_from_markers('data_scale', request)
      mean = value_from_markers('data_mean', request)
  
      with NumpyRNGContext(DEFAULTS['seed']):
          data = np.random.normal(loc=mean, size=[size, size], scale=scale)
  
      return CCDData(data, unit=u.adu)
  
new_contents: from __future__ import (absolute_import, division, print_function,
                          unicode_literals)
  
  import numpy as np
  
  from astropy.tests.helper import pytest
  from astropy import units as u
  from astropy.utils import NumpyRNGContext
  
  from ..ccddata import CCDData
  
  # If additional pytest markers are defined the key in the dictionary below
  # should be the name of the marker.
  DEFAULTS = {
      'seed': 123,
      'data_size': 100,
      'data_scale': 1.0,
      'data_mean': 0.0
  }
  
  DEFAULT_SEED = 123
  DEFAULT_DATA_SIZE = 100
  DEFAULT_DATA_SCALE = 1.0
  
  
  def value_from_markers(key, request):
      try:
          val = request.keywords[key].args[0]
      except KeyError:
          val = DEFAULTS[key]
      return val
  
  
  @pytest.fixture
  def ccd_data(request):
      """
      Return a CCDData object with units of ADU.
  
      The size of the data array is 100x100 but can be changed using the marker
      @pytest.mark.data_size(N) on the test function, where N should be the
      desired dimension.
  
      Data values are initialized to random numbers drawn from a normal
      distribution with mean of 0 and scale 1.
  
      The scale can be changed with the marker @pytest.marker.scale(s) on the
      test function, where s is the desired scale.
  
      The mean can be changed with the marker @pytest.marker.scale(m) on the
      test function, where m is the desired mean.
      """
      size = value_from_markers('data_size', request)
      scale = value_from_markers('data_scale', request)
      mean = value_from_markers('data_mean', request)
  
      with NumpyRNGContext(DEFAULTS['seed']):
          data = np.random.normal(loc=mean, size=[size, size], scale=scale)
  
      fake_meta = {'my_key': 42, 'your_key': 'not 42'}
      ccd = CCDData(data, unit=u.adu)
      ccd.header = fake_meta
      return ccd
  
subject: Add a little metadata to the default test image