def getEdge(self, _id):
try:<EOL><INDENT>edge = self.neograph.relationships.get(_id)<EOL><DEDENT>except client.NotFoundError:<EOL><INDENT>return None<EOL><DEDENT>return Edge(edge)<EOL>
Retrieves an existing edge from the graph
        @params _id: Edge unique identifier

        @returns The requested Edge or None