@abc.abstractmethod<EOL><INDENT>def get_proficiency(self, proficiency_id):<DEDENT>
return<EOL>
Gets the ``Proficiency`` specified by its ``Id``.

        :param proficiency_id: the ``Id`` of the ``Proficiency`` to retrieve
        :type proficiency_id: ``osid.id.Id``
        :return: the returned ``Proficiency``
        :rtype: ``osid.learning.Proficiency``
        :raise: ``NotFound`` -- no ``Proficiency`` found with the given ``Id``
        :raise: ``NullArgument`` -- ``proficiency_id`` is ``null``
        :raise: ``OperationFailed`` -- unable to complete request
        :raise: ``PermissionDenied`` -- authorization failure

        *compliance: mandatory -- This method must be implemented.*