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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 full_id(self):
 """Return the full_id for this Async. Consists of the parent id, id and context id. """

        full_id = ""

        if self.parent_id:
            full_id = ":".join([self.parent_id, self.id])
        else:
            full_id = self.id

        if self.context_id:
            full_id = "|".join([full_id, self.context_id])

        return full_id