Theatre (3 points)
==================

A theatre has gathered data concerning the occupancy (number of sold
tickets) of its hall for several plays and several sessions for each
play. These data are represented with a nested :py:class:`list`: in
each sublist of it there is the name of a play (:py:class:`str`) and
the occupancy (:py:class:`int`) for several sessions in which this
play has been performed. For example, the sublist ``['Mary Poppins',
414, 232, 119]`` shows that the play with name ``'Mary Poppins'`` has
been performed in three sessions with an occupancy of 414, 232 and 119
respectively.

We define the *occupancy average* of a play as the occupancy average
of its sessions and the *occupancy rate* of a play as the percentage
of the *occupancy average* with respect to the hall capacity. For the
previous sublist example and a hall capacity of ``478``, the *occupancy
average* can be computed as ``(414 + 232 + 119)/3`` which is
``255.0``, and the *occupancy rate* can be computed as
``255.0/478*100`` which is ``53.34%``.

Write function :py:func:`theatre` that takes a nested :py:class:`list`
as that described in the first paragraph, the capacity of the theatre
hall (:py:class:`int`) and a percentage (:py:class:`float`). This
function returns a :py:class:`list` with the play names
(:py:class:`str`) of those plays with an *occupancy rate* 
less than the given percentage. The ordering of the play names in the
output list must be the same as in the input list.

For the previous example and a given percentage of ``60%`` the name of
the play ``'Mary Poppins'`` would be included in the output list.

Save this function in file ``theatre.py``.

Examples:

.. literalinclude:: test-theatre.txt
      :language: python
      :lines: 3-17

.. note::

   More tests are provided in file :download:`test-theatre.txt`.