<｜begin▁of▁sentence｜>### Instruction:
As an electrical technician, let's say you're working on a project that involves designing and installing a network of sensors in a building for monitoring electrical usage. You're using Python with the Cairo library to draw the layout of the sensors on a graphical interface. Now, you need to convert the local coordinates of each sensor, starting from the origin (0, 0), to the context coordinates used by Cairo for accurate placement on the graphical interface. You're looking for a method or function within the Cairo library that can assist in this coordinate transformation.
### Response:
import igraph as ig
import cairo
from igraph.drawing.coord import DescartesCoordinateSystem

# Assume we have a graph and a Cairo context
width, height = 600, 600
surface = cairo.ImageSurface(cairo.FORMAT_ARGB32, width, height)
ctx = cairo.Context(surface)

# Set up the graph plotting
graph = ig.Graph.Famous('petersen')
layout = graph.layout('kk')
plot = ig.Plot(surface, bbox=(width, height), background='white')
plot.add(graph, layout=layout)

# Set up the coordinate system with specified width and height
coord_sys = DescartesCoordinateSystem(bbox=(width, height))

# Convert local coordinate (0, 0) to context coordinates
context_x, context_y = coord_sys.local_to_context(0, 0)
print(f'Context coordinates: ({context_x}, {context_y})')

# Complete the drawing and save the image
plot.redraw()
surface.write_to_png('graph_with_cairo.png')
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