old_contents: from pyxtf.xtf_ctypes import *
  from pyxtf.xtf_io import xtf_read
new_contents: from pyxtf.xtf_ctypes import *
  from pyxtf.xtf_io import xtf_read, channel_count, concatenate_channel
  
  
subject: Add channel_count and concatenate_channel to __init__