class_docstr: A persistent bag/multiset type.
  
  Requires elements to be hashable, and allows duplicates, but has no
  ordering. Bags are hashable.
  
  Do not instantiate directly, instead use the factory functions :py:func:`b`
  or :py:func:`pbag` to create an instance.
  
  Some examples:
  
  >>> s = pbag([1, 2, 3, 1])
  >>> s2 = s.add(4)
  >>> s3 = s2.remove(1)
  >>> s
  pbag([1, 1, 2, 3])
  >>> s2
  pbag([1, 1, 2, 3, 4])
  >>> s3
  pbag([1, 2, 3, 4])
docstr: Return an iterator of all elements, including duplicates.
  
  >>> list(pbag([1, 1, 2]))
  [1, 1, 2]
  >>> list(pbag([1, 2]))
  [1, 2]
docstr_tok: ["Return","an","iterator","of","all","elements",",","including","duplicates",".",">",">",">","list","(","pbag","(","[","1",",","1",",","2","]",")",")","[","1",",","1",",","2","]",">",">",">","list","(","pbag","(","[","1",",","2","]",")",")","[","1",",","2","]"]
code: def __iter__(self):
      """
      Return an iterator of all elements, including duplicates.
  
      >>> list(pbag([1, 1, 2]))
      [1, 1, 2]
      >>> list(pbag([1, 2]))
      [1, 2]
      """
      for elt, count in self._counts.iteritems():
          for i in range(count):
              yield elt
  
imports: from collections.abc import Container, Iterable, Sized, Hashable
  from functools import reduce
  from typing import Generic, TypeVar
  from pyrsistent._pmap import pmap
label_desc: Use image node_id 7 for calling the PBag obj's underlying member method code with example usage: obj.__iter__() without return types