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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 pin_in_object_store(obj):
 """Pin an object in the object store. It will be available as long as the pinning process is alive. The pinned object can be retrieved by calling get_pinned_object on the identifier returned by this call. """


    obj_id = ray.put(_to_pinnable(obj))
    _pinned_objects.append(ray.get(obj_id))
    return "{}{}".format(PINNED_OBJECT_PREFIX,
                         base64.b64encode(obj_id.binary()).decode("utf-8"))