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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_orgas(self):
 """Return the list of pk for all orgas"""


        r = self._request('orgas/')
        if not r:
            return None

        retour = []

        for data in r.json()['data']:
            o = Orga()
            o.__dict__.update(data)
            o.pk = o.id

            retour.append(o)

        return retour