Holidays (3 points)
===================

A travel agency saves the booked trips in a file. There is a header
line with the name of the travel and then a line for each
customer. Each of these lines has the following data separated by a
hyphen (``-``): the customer name (:class:`str`), the room type
(:class:`str`) that can be ``'double'`` or ``'single'``, the number of
hotel nights (:class:`int`) and a variable number of names
(:class:`str`) for extra excursions booked by this customer. There is
also a dictionary (:class:`dict`) for extra excursions in which the
key is the name of the excursion (:class:`str`) and the value is its
price (:class:`int`).

Write function :py:func:`holidays` that takes the name of an input
file (:class:`str`) and a dictionary of extra excursions prices as
those described, it also takes the hotel price for a night
(:class:`int`) and a name of an output file (:class:`str`). This
function must create an (output) file with the given name that will
have a line for each customer with the name of the customer
(:class:`str`), a colon and a space (``': '``) and the total amount
that this customer must pay (:class:`int`) followed by the euro symbol
(``'€'``). The total amount for a customer includes the price for the
hotel nights and the extra excursions booked by them and it must be
the integer part of the computed result. The cost of a single room is
a 20\% more expensive than the double one.

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

Example:

For a data file with the name ``'greece.txt'`` with the following content:

.. literalinclude:: solution/greece.txt
   :language: text
	   
and executing the following statements:

.. literalinclude:: test-holidays.txt
   :language: python
   :lines: 6-8


an output file with name ``'gr_bills.txt'`` will be created with the
following content:

.. literalinclude:: solution/gr_bills.txt
   :language: text

.. note::

   Tests for automatic debugging are provided in file :download:`test-holidays.txt`.