Forum
=====

We have a file with the statistics concerning a forum, where each line
represents a user and contains the username (:class:`str`), the number
of posts in the forum, the number of read messages and the number of
sent comments (three :class:`int`), in this order and separated by a
semicolon (``';'``). An example of this kind of file is file
:download:`data_forum.txt <examples/data_forum.txt>` with this
content:

      .. literalinclude:: examples/data_forum.txt
         :language: python3
         :lines: 1-

Save all functions into the file named ``forum.py``.
		 
#. Write the function :py:func:`no_opinion` that given the name of a
   file (:class:`str`) with the format shown, returns a :class:`list`
   with the usernames (:class:`str`) of those users that have not made
   any comments. Examples:
      
      .. literalinclude:: test-no_opinion.txt
         :language: python3
         :lines: 3-

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

#. There was a problem during the user registration process. Usernames
   must have at least 6 characters and we want to know if there are
   any errors. Write the function :py:func:`wrong_name` that given the
   name of a file like the previously shown (:class:`str`), returns
   ``True`` if there is any username with less than 6 characters and
   ``False`` otherwise. Examples:
 
      .. literalinclude:: test-wrong_name.txt
         :language: python3
         :lines: 3-

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

#. Write the function :py:func:`entries` that given the name of a file
   as described above (:class:`str`), the name of another file
   (:class:`str`) and a number (:class:`int`), creates this second
   file and writes in it those users who have made a number of entries
   to the forum greater than or equal to the given number. In the new
   created file there is a line for each user with the username and
   number of entries of that user separated by a space.

   With the data file ``data_forum.txt``, shown at the beginning, and
   executing this statement:

      .. literalinclude:: test-entries.txt
         :language: python3
         :lines: 7

   A new file with name  ``visitors.txt`` will be created with this
   content:

      .. literalinclude:: examples/visitors.txt
         :language: python3
         :lines: 1-

   .. note::
        Tests for automatic debugging are provided in file :download:`test-entries.txt <test-entries.txt>`
	
.. rubric:: Solution

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