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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 people(self):
        '''Dictionary of people on the project, keyed by id'''
        if self.cache['people']: return self.cache['people']
        people_xml = self.bc.people_within_project(self.id)
        for person_node in ET.fromstring(people_xml).findall('person'):
            p = Person(person_node)
            self.cache['people'][p.id] = p
        return self.cache['people']