code: def mergeFeatures(lst):
      assert lst
      self = otTables.Feature()
      self.FeatureParams = None
      self.LookupListIndex = mergeLookupLists(
          [l.LookupListIndex for l in lst if l.LookupListIndex]
      )
      self.LookupCount = len(self.LookupListIndex)
      return self
  
imports: from fontTools import ttLib
  from fontTools.ttLib.tables.DefaultTable import DefaultTable
  from fontTools.ttLib.tables import otTables
  from fontTools.merge.base import add_method, mergeObjects
  from fontTools.merge.util import *
  import logging
label_desc: Use image node_id 2 for calling a global function with example usage: mergeFeatures(lst) and returns: self