.. role:: python(code)
   :language: python

.. index::
   itertools


..
   `itertools <ex:itertools>`_

.. _`sec:itertools`:

Iterator tools
--------------


The `iterator tools <https://docs.python.org/3/library/itertools.html#>`_  :python:`itertools` module especially regroups several combinatoric iterators 
which can be useful. 

.. admonition:: Exercise (easy)

   In the :ref:`project assignment <sec:architecture>` exercise, the student picking order matters. 
   The first to pick is certain to get his preferred choice, the second is certain to get at least his second preferred, etc 
   Create a generator which yields every picking order possible.

.. _`ex:itertools`:

.. collapse:: Correction

   .. literalinclude:: ../../../../src/tools_methods/useful_modules/iterators.py
      :pyobject: yield_all_possible_choosers_order
      :name: yield_all_possible_choosers_order
      :linenos:    
      :caption: src   

   .. literalinclude:: ../../../../tests/tools_methods/useful_modules/test_iterators.py
      :pyobject: test_yield_all_possible_choosers_order
      :name: test_yield_all_possible_choosers_order
      :linenos:    
      :caption: tests