Initial_list
============

Save the following function into a file named ``initials.py``.

Write the function :py:func:`initials` that takes a text
(:class:`str`), and returns a dictionary (:class:`dict`) where the key
is a lowercase letter and the value is a list with all the words that
begin with this letter found in the given text. The text only contains
letters, which may be upper or lowercase, and spaces. The dictionary
will not contain any letter that does not appear as an initial of a
word in the given text (incomplete dictionary). Words in the
dictionary lists will be lowercase, in alphabetical order and
without repetitions. Examples:
                 
.. literalinclude:: test-initials.txt
       :language: python
       :lines: 3-11
   
.. note::
      More tests are provided in file :download:`test-initials.txt`.
      
.. rubric:: Solution
      
A solution of this function is provided in file
:download:`initials.py<solutions/initials.py>`.