#press alt x
kmi = km.keymap_items.new('moveandscrubkeyframes', 'X', 'PRESS', alt=True)

#copy keyframe of selected
'pose.copy'
#delete keyframe of selected
'anim.keyframe_delete'

#hotkey only active while alt x is pressed
kmi = km.keymap_items.new('screen.frame_offset', 'WHEELDOWNMOUSE', 'PRESS')
kmi_props_setattr(kmi.properties, 'delta', 1)

kmi = km.keymap_items.new('screen.frame_offset', 'WHEELUPMOUSE', 'PRESS')
kmi_props_setattr(kmi.properties, 'delta', -1)


#release alt x
kmi = km.keymap_items.new('moveandscrubkeyframes', 'X', 'Release', alt=True)

#paste keyframe
'pose.paste'