Currencies
==========

Save all functions into the same file named  :file:`currencies.py`.

We define a first string format as:

``amount currency``

where ``amount`` does not contain decimals, ``currency`` always
contains three characters and where the separation between ``amount``
and ``currency`` is always a single whitespace. Example: '235 EUR'

We define a second string format as:

``employee_type:amount currency``

where ``employee_type`` is a single character meaning: 'D' (managing
director), 'P' (project manager) or 'T' (technician), ``amount`` does
not contain decimals, ``currency`` always contains three characters
and where the separation between ``employee_type`` and ``amount`` is
always a colon and the separation between ``amount`` and ``currency``
is a single whitespace. Example: 'D:230 EUR'

#. Write function :py:func:`extract_currency` that takes a string in
   the first format, and returns a new string with the currency. If
   the given string is empty, it returns also an empty string. Example:

   .. literalinclude:: test-currencies1.txt
      :language: python3
      :lines: 3-
              
   .. note::

      More tests are provided in file :download:`test-currencies1.txt
      <test-currencies1.txt>`

#. Write function :py:func:`extract_amount` that takes a string in the
   first format, and returns the corresponding amount (``int``). If
   the given string is empty, it returns -1. Example:

   .. literalinclude:: test-currencies2.txt
      :language: python3
      :lines: 3-

   .. note::

       More tests are provided in file :download:`test-currencies2.txt
       <test-currencies2.txt>`

#. Write function :py:func:`employee_cost` that takes a string in the
   second format, and returns a ``float`` with the cost amount in
   euros, taking into account that when the employee is a managing
   director, the returning cost is 0.0. There are only two possible
   currencies other than euros, 'USD' and 'AUD' and the fix conversion
   to be applied will be: 1USD = 0.9EUR and 1AUD = 0.65EUR. This
   function must call the two previous functions
   :py:func:`extract_currency` and :py:func:`extract_amount`.
   Example:

   .. literalinclude:: test-currencies3.txt
      :language: python3
      :lines: 3-
  
   .. note::

      More tests are provided in file :download:`test-currencies3.txt <test-currencies3.txt>`

#. Write function :py:func:`convert_cost` that takes a string in the
   second format, and returns another string with the following
   format:

   ``amount EUR``

   where ``amount`` is the integer part of the amount in the given
   string, converted to euros, taking into account that when the
   employee is a managing director, the returning cost is 0.0. There
   are only two possible currencies other than euros, 'USD' and 'AUD'
   and the fix conversion to be applied will be: 1USD = 0.9EUR and
   1AUD = 0.65EUR. This function must call the previous one
   :py:func:`employee_cost`. Example:

   .. literalinclude:: test-currencies4.txt
      :language: python3
      :lines: 3-
 
   .. note::

      More tests are provided in file :download:`test-currencies4.txt <test-currencies4.txt>`   

.. rubric:: Solution

A solution of these functions is provided in file
:download:`currencies.py <solutions/currencies.py>`