text: 
  from lib2to3 import fixer_base, pytree, patcomp
  from lib2to3.pgen2 import token
  from lib2to3.fixer_util import LParen, RParen, Comma
  
  """
  Fixes:
      open(a, b, encoding=)
  into:
      open(a, b)
  """
  
  class FixOpen(fixer_base.BaseFix):
      PATTERN = """
          power< 'open' trailer< '(' arglist< any ',' any
              comma=',' enc=argument< 'encoding' '=' any > > ')' > >
      """
  
      def transform(self, node, results):
          results['comma'].remove()
          results['enc'].remove()
          return node
  