Jupyter Notebook extension for graph visualization

[yecol]

Is your feature request related to a problem? Please describe.

Graph visualization is an essential part for a graph computing platform. As the first step, we may want a module to visualize the graph data.

Describe the solution you'd like

• implement this feature via a Jupyter notebook extension in the location /python/jupyter
• visualize the graph data in the result cell when the draw functions are invoked.
• the draw APIs:

  
  # assume the g is a Graph in GraphScope.
  # draw the whole graph. (maybe cascaded if the graph is huge.)
  g.draw()

draw selected vertices and their induced subgraph

g.draw(vertices=[1,2,3,4])

draw induced subgraph with hop extension

g.draw(vertices=[1, 2 ,3, 4], hop=2)

draw a subgraph with selected labels.

g.draw(vlabel=“students”, elabel=“friends”)

draw the graph with captions

label.e, label.v, label

id.e, id.v, id

prop.XXX

e.g.,

g.draw(caption=“label:e”) g.draw(caption="prop.name")

pass the args with a dict.

g.draw(config=Dict())

**Describe alternatives you've considered**
A clear and concise description of any alternative solutions or features you've considered.

**Additional context**
Add any other context or screenshots about the feature request here.

[howie6879]

Great feature, how about adding query support for gremlin?

g.draw(gremlin_sql = "g.V()")

[yecol]

Good suggestion! We will consider this on the next step. :)

[sighingnow]

Reopen since #127 is just a startpoint for the visualization task.