Fixed Linux/OSX crash

kcc/KCC_gui.py

@@ -36,7 +36,7 @@ from subprocess import STDOUT, PIPE
 from PyQt5 import QtGui, QtCore, QtWidgets
 from xml.dom.minidom import parse
 from html.parser import HTMLParser
-from psutil import virtual_memory, Popen, Process, BELOW_NORMAL_PRIORITY_CLASS
+from psutil import virtual_memory, Popen, Process
 from .shared import md5Checksum
 from . import comic2ebook
 from . import kindlesplit
@@ -1100,6 +1100,7 @@ class KCCGUI(KCC_ui.Ui_KCC):
             self.tray.show()
             MW.addTrayMessage.connect(self.tray.addTrayMessage)
             # Decrease priority to increase system responsiveness during conversion
+            from psutil import BELOW_NORMAL_PRIORITY_CLASS
             self.p = Process(os.getpid())
             self.p.nice(BELOW_NORMAL_PRIORITY_CLASS)
             self.p.ionice(1)