def get_proficiency_lookup_session_for_objective_bank(self, objective_bank_id, proxy):
if not objective_bank_id:<EOL><INDENT>raise NullArgument<EOL><DEDENT>if not self.supports_proficiency_lookup():<EOL><INDENT>raise Unimplemented()<EOL><DEDENT>try:<EOL><INDENT>from . import sessions<EOL><DEDENT>except ImportError:<EOL><INDENT>raise OperationFailed()<EOL><DEDENT>proxy = self._convert_proxy(proxy)<EOL>try:<EOL><INDENT>session = sessions.ProficiencyLookupSession(objective_bank_id=objective_bank_id, proxy=proxy, runtime=self._runtime)<EOL><DEDENT>except AttributeError:<EOL><INDENT>raise OperationFailed()<EOL><DEDENT>return session<EOL>
Gets the ``OsidSession`` associated with the proficiency lookup service for the given objective bank.

        :param objective_bank_id: the ``Id`` of the obective bank
        :type objective_bank_id: ``osid.id.Id``
        :param proxy: a proxy
        :type proxy: ``osid.proxy.Proxy``
        :return: a ``ProficiencyLookupSession``
        :rtype: ``osid.learning.ProficiencyLookupSession``
        :raise: ``NotFound`` -- no ``ObjectiveBank`` found by the given ``Id``
        :raise: ``NullArgument`` -- ``objective_bank_id`` or ``proxy`` is ``null``
        :raise: ``OperationFailed`` -- unable to complete request
        :raise: ``Unimplemented`` -- ``supports_proficiency_lookup()`` or ``supports_visible_federation()`` is ``false``

        *compliance: optional -- This method must be implemented if ``supports_proficiency_lookup()`` and ``supports_visible_federation()`` are ``true``*