content: """
  Helper functions for determining which tests to skip.
  """
  
  __authors__ = "Ian Goodfellow"
  __copyright__ = "Copyright 2010-2012, Universite de Montreal"
  __credits__ = ["Ian Goodfellow"]
  __license__ = "3-clause BSD"
  __maintainer__ = "LISA Lab"
  __email__ = "pylearn-dev@googlegroups"
  from nose.plugins.skip import SkipTest
  import os
  from theano.sandbox import cuda
  
  scipy_works = True
  try:
      import scipy
  except ImportError:
      # pyflakes gets mad if you set scipy to None here
      scipy_works = False
  
  sklearn_works = True
  try:
      import sklearn
  except ImportError:
      sklearn_works = False
  
  h5py_works = True
  try:
      import h5py
  except ImportError:
      h5py_works = False
  
  matplotlib_works = True
  try:
      from matplotlib import pyplot
  except ImportError:
      matplotlib_works = False
  
  
  def skip_if_no_data():
      if 'PYLEARN2_DATA_PATH' not in os.environ:
          raise SkipTest()
  
  
  def skip_if_no_scipy():
      if not scipy_works:
          raise SkipTest()
  
  
  def skip_if_no_sklearn():
      if not sklearn_works:
          raise SkipTest()
  
  
  def skip_if_no_gpu():
      if cuda.cuda_available == False:
          raise SkipTest('Optional package cuda disabled.')
  
  
  def skip_if_no_h5py():
      if not h5py_works:
          raise SkipTest()
  
  
  def skip_if_no_matplotlib():
      if not matplotlib_works:
          raise SkipTest("matplotlib and pyplot are not available")
  