Graph implementation using linkedlists

Here's my python class
(Includes class Node and class Graph)
https://raw.githubusercontent.com/prabushitha/DataStructures/master/Graph/GraphAL.py

Usage
#After copying/importing above 2 classes to your code

#Creating a new graph
graph = Graph()

#Adding a vertex. e.g add 2 vertexes A and B
graph.addVertex("A")
graph.addVertex("B")

#Adding an edge between 2 vertexes 
graph.addEdge("A","B")

#Check whether there's an edge between 2 vertexes. e.g from A to B (returns True/False)
graph.isEdge("A","C")
#Check whether there's a path from one vertex to another. e.g from A to B (returns True/False)
graph.isPath("D","B")