Interval
========

Write a function ``interval(li, ls, n, closed)``
that takes 4 values: the upper and lower limits of an interval and
a number (3 real numbers) and a boolean containing
``True`` if the interval is closed and
``False`` if it is open,
and returns  ``True`` if that number is inside the interval
and ``False`` otherwise.

Save the function in the file ``interval.py``. This function must pass the doctest:
   
   .. literalinclude:: interval.txt
      :language: python3
      :lines: 2-

   .. note::

      You can download the file with tests :download:`interval.txt <interval.txt>`

.. rubric:: Solution

You have solutions in the file :download:`interval.py
<solutions/interval.py>`