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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_assessment_session_for_bank(self, bank_id, proxy):
 """Gets an ``AssessmentSession`` which is responsible for performing assessments for the given bank ``Id``. arg: bank_id (osid.id.Id):
 the ``Id`` of a bank arg: proxy (osid.proxy.Proxy):
 a proxy return: (osid.assessment.AssessmentSession) - an assessment session for this service raise: NotFound - ``bank_id`` not found raise: NullArgument - ``bank_id`` or ``proxy`` is ``null`` raise: OperationFailed - unable to complete request raise: Unimplemented - ``supports_assessment()`` is ``false`` *compliance: optional -- This method must be implemented if ``supports_assessment()`` is ``true``.* """

        if not self.supports_assessment():
            raise errors.Unimplemented()
        ##
        # Also include check to see if the catalog Id is found otherwise raise errors.NotFound
        ##
        # pylint: disable=no-member
        return sessions.AssessmentSession(bank_id, proxy, self._runtime)