old_contents: import os
  
  with open("src/conf.lua.bak") as f:
      conf = f.read()
  
      conf = conf.replace("t.release           = false",
                          "t.release           = true")
      conf = conf.replace("ac1c2db50f1332444fd0cafffd7a5543",
                          os.environ["MIXPANEL_TOKEN"])
  
      with open("src/conf.lua", "w") as g:
          g.write(conf)
  
new_contents: import os
  
  with open("src/conf.lua.bak") as f:
      conf = f.read()
  
      conf = conf.replace("t.release           = false",
                          "t.release           = true")
  
      if "MIXPANEL_TOKEN" in os.environ:
          conf = conf.replace("ac1c2db50f1332444fd0cafffd7a5543",
                              os.environ["MIXPANEL_TOKEN"])
  
      with open("src/conf.lua", "w") as g:
          g.write(conf)
  
subject: Build releases even without MIXPANEL_TOKEN