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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 host_chairs(self):
        '''Returns a list of members that chair the host committee,
        including "co-chair" and "chairperson." This could concievalby
        yield a false positive if the person's title is 'dunce chair'.
        '''
        chairs = []
        # Host is guaranteed to be a committe or none.
        host = self.host()
        if host is None:
            return
        for member, full_member in host.members_objects:
            if 'chair' in member.get('role', '').lower():
                chairs.append((member, full_member))
        return chairs