code: def next(self):
      if self._pushed:
          return self._pushed.pop()
      else:
          # May raise StopIteration
          return six.advance_iterator(self._it)
  
imports: import sys
  import numpy
  import six
  from six.moves import cStringIO
  from .compat import optional_dep_ok
label_desc: Use image node_id 4 for calling the PushbackAdapter obj's underlying member method code with example usage: obj.next() and returns: self, six