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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 as_json(self, entity_url, context=None):
 """Method takes a entity uri and attempts to return the Fedora Object as a JSON-LD. Args: entity_url(str):
 Fedora Commons URL of Entity context(None):
 Returns JSON-LD with Context, default is None Returns: str: JSON-LD of Fedora Object """

        try:
            urllib.request.urlopen(entity_url)
        except urllib.error.HTTPError:
            raise ValueError("Cannot open {}".format(entity_url))
        entity_graph = self.read(entity_url)
        entity_json = json.loads(
            entity_graph.serialize(
                format='json-ld',
                context=context).decode())
        return json.dumps(entity_json)