text: """NSActivityOptions
  
  https://developer.apple.com/library/content/documentation/Performance/Conceptual/power_efficiency_guidelines_osx/PrioritizeWorkAtTheAppLevel.html
  
  License
  -------
  Incorporates code from `appnope <https://github.com/minrk/appnope>`_ under
  2-clause BSD, copyright (c) 2013, Min Ragan-Kelley
  
  All rights reserved.
  
  Redistribution and use in source and binary forms, with or without
  modification, are permitted provided that the following conditions are met:
  
  Redistributions of source code must retain the above copyright notice, this
  list of conditions and the following disclaimer.
  
  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
  ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  """
  # cf. https://github.com/ipython/ipython/tree/master/IPython/terminal/pt_inputhooks/osx.py
  import ctypes.util
  
  objc = ctypes.cdll.LoadLibrary(ctypes.util.find_library('objc'))
  
  void_p = ctypes.c_void_p
  ull = ctypes.c_uint64
  
  objc.objc_getClass.restype = void_p
  objc.sel_registerName.restype = void_p
  objc.objc_msgSend.restype = void_p
  objc.objc_msgSend.argtypes = [void_p, void_p]
  
  msg = objc.objc_msgSend
  n = objc.sel_registerName
  c = objc.objc_getClass
  
  # constants from Foundation
  NSActivityIdleDisplaySleepDisabled = (1 << 40)
  NSActivityIdleSystemSleepDisabled = (1 << 20)
  NSActivitySuddenTerminationDisabled = (1 << 14)
  NSActivityAutomaticTerminationDisabled = (1 << 15)
  NSActivityUserInitiated = (0x00FFFFFF | NSActivityIdleSystemSleepDisabled)
  NSActivityUserInitiatedAllowingIdleSystemSleep = (NSActivityUserInitiated & ~NSActivityIdleSystemSleepDisabled)
  NSActivityBackground = 0x000000FF
  NSActivityLatencyCritical = 0xFF00000000
  
  
  def _utf8(s):
      return s if isinstance(s, bytes) else s.encode('utf8')
  
  
  def beginActivityWithOptions(options, reason=""):
      """Begin an activity using the given options and reason
  
      Returns
      -------
      activity : int
          Identifier for the activity.
  
      Notes
      -----
      Indicate completion of the activity by calling :func:`end_activity`,
      passing the returned identifier as the argument.
      """
      reason = msg(c(b'NSString'), n(b'stringWithUTF8String:'), _utf8(reason))
      info = msg(c(b'NSProcessInfo'), n(b'processInfo'))
      return msg(info, n(b'beginActivityWithOptions:reason:'), ull(options),
                 void_p(reason))
  
  
  def end_activity(activity):
      """end a process activity assertion
  
      Parameters
      ----------
      activity : int
          Identifier for the activity, returned by
          :func:`beginActivityWithOptions`.
      """
      info = msg(c(b'NSProcessInfo'), n(b'processInfo'))
      msg(info, n(b'endActivity:'), void_p(activity))
  
  
  def begin_activity(options=NSActivityUserInitiated, reason='Eelbrain'):
      """Disable macOS system sleep"""
      return beginActivityWithOptions(options, reason)
  