def build(self):
mainPanel = MainPanel()
vertex1 = Vertex(pos = (100,100), radius = 25)
vertex2 = Vertex(pos = (200,200), radius = 25)
edge = Edge()
edge.setVertices(vertex1, vertex2)
mainPanel.add_widget(edge)
mainPanel.add_widget(vertex1)
mainPanel.add_widget(vertex2)
return mainPanel
