old_contents: import os
  import sys
  import marshal
  
  
  if sys.hexversion < 0x03030000:
      raise ImportError('python >= 3.3 required')
  
  if sys.implementation.cache_tag is None:
      raise ImportError('python implementation does not use bytecode')
  
  PY_TAG      = sys.implementation.cache_tag
  PY_VERSION  = sys.hexversion
  BUNDLE_DIR  = os.path.join(__path__[0], 'bundle')
  BUNDLE_FILE = os.path.join(BUNDLE_DIR, PY_TAG + '.dgbundle')
  
  if not os.path.exists(BUNDLE_FILE):
      raise ImportError('python implementation {!r} not supported'.format(PY_TAG))
  
  with open(BUNDLE_FILE, 'rb') as _fd:
      for _c in marshal.load(_fd):
          eval(_c)
  
  del _c
  del _fd
  
new_contents: import os
  import sys
  import marshal
  
  
  if not hasattr(sys, 'implementation'):
      raise ImportError('python >= 3.3 required')
  
  if sys.implementation.cache_tag is None:
      raise ImportError('python implementation does not use bytecode')
  
  PY_TAG      = sys.implementation.cache_tag
  PY_VERSION  = sys.hexversion
  BUNDLE_DIR  = os.path.join(__path__[0], 'bundle')
  BUNDLE_FILE = os.path.join(BUNDLE_DIR, PY_TAG + '.dgbundle')
  
  if not os.path.exists(BUNDLE_FILE):
      raise ImportError('python implementation {!r} not supported'.format(PY_TAG))
  
  with open(BUNDLE_FILE, 'rb') as _fd:
      for _c in marshal.load(_fd):
          eval(_c)
  
  del _c
  del _fd
  
subject: Use a different way of ensuring 3.3+.