<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def getVerifier(self):
 """Returns the user that verified the whole Analysis Request. Since the verification is done automatically as soon as all the analyses it contains are verified, this function returns the user that verified the last analysis pending. """

        wtool = getToolByName(self, 'portal_workflow')
        mtool = getToolByName(self, 'portal_membership')

        verifier = None
        # noinspection PyBroadException
        try:
            review_history = wtool.getInfoFor(self, 'review_history')
        except:  # noqa FIXME: remove blind except!
            return 'access denied'

        if not review_history:
            return 'no history'
        for items in review_history:
            action = items.get('action')
            if action != 'verify':
                continue
            actor = items.get('actor')
            member = mtool.getMemberById(actor)
            verifier = member.getProperty('fullname')
            if verifier is None or verifier == '':
                verifier = actor
        return verifier