<｜begin▁of▁sentence｜>### Instruction:
As a legal mediator, I often find myself needing to illustrate complex ideas in a clear and concise manner during negotiation sessions. Recently, I encountered a situation where visualizing the hierarchy of responsibilities within a company became crucial to resolving a dispute. 

The company in question had a hierarchical structure resembling a tree, with five key departments represented as vertices. Each department had two sub-departments reporting to it, forming a clear tree hierarchy. 

To aid in our negotiation process, I needed to create a customized visualization of this hierarchical structure. Using the CairoVertexDrawer API, I aimed to plot the vertices of the graph within a bounding box of 300x300 pixels. This visual representation would help all parties involved to better understand the organizational structure and facilitate smoother discussions.
### Response:
from igraph import Graph, plot
from igraph.drawing import BoundingBox
from igraph.drawing.cairo import CairoVertexDrawer, CairoContextManager

# Create your graph
g = Graph.Tree(5, 2)

# Define the bounding box with width and height
bbox = BoundingBox(300, 300)

# Layout of the graph
layout = g.layout('auto')

# Initialize the Cairo context manager (surface and context)
with CairoContextManager((300, 300)) as (surface, context):
    # Create a CairoVertexDrawer instance with the context and bounding box
    vertex_drawer = CairoVertexDrawer(context=context, bbox=bbox, palette=None, layout=layout)
    
    # Use the vertex_drawer to customize the plotting of vertices
    # For example, loop through vertices and draw them
    for v in g.vs:
        vertex_drawer.draw(v, (layout[v.index][0], layout[v.index][1]))
    
    # After drawing, save the plot to a file
    surface.write_to_png('graph.png')
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