class_docstr: Merges networks from multiple CFF files into one new CFF file.
  
  Example
  -------
  
  >>> import nipype.interfaces.cmtk as cmtk
  >>> mrg = cmtk.MergeCNetworks()
  >>> mrg.inputs.in_files = ['subj1.cff','subj2.cff']
  >>> mrg.run()                  # doctest: +SKIP
code: def _run_interface(self, runtime):
      import cfflib as cf
  
      extracted_networks = []
  
      for i, con in enumerate(self.inputs.in_files):
          mycon = cf.load(con)
          nets = mycon.get_connectome_network()
          for ne in nets:
              # here, you might want to skip networks with a given
              # metadata information
              ne.load()
              contitle = mycon.get_connectome_meta().get_title()
              ne.set_name(
                  str(i) + ": " + contitle + " - " + ne.get_name()
              )
              ne.set_src(ne.get_name())
              extracted_networks.append(ne)
  
      # Add networks to new connectome
      newcon = cf.connectome(
          title="All CNetworks", connectome_network=extracted_networks
      )
      # Setting additional metadata
      metadata = newcon.get_connectome_meta()
      metadata.set_creator("My Name")
      metadata.set_email("My Email")
  
      _, name, ext = split_filename(self.inputs.out_file)
      if not ext == ".cff":
          ext = ".cff"
      cf.save_to_cff(newcon, op.abspath(name + ext))
  
      return runtime
  
imports: import os
  import os.path
  import datetime
  import string
  import networkx
  from ...utils.filemanip import split_filename
  from ..base import BaseInterfaceInputSpec, traits, File, TraitedSpec, InputMultiPath, isdefined
  from .base import CFFBaseInterface, have_cfflib
label_desc: Use image node_id 1 for calling the MergeCNetworks obj's underlying member method code with example usage: obj._run_interface(runtime) and returns: runtime