<｜begin▁of▁sentence｜>### Instruction:
Given rectangle1 with its two vertex coordinates being (10, 10) and (30, 30), and rectangle2 with its two vertex coordinates being (20, 20) and (50, 50), can you use Rectangle.union function in igraph to calculate the smallest rectangle that contains both rectangles and print its coordinates?
### Response:
from igraph.drawing.utils import Rectangle

# create two rectangles
r1 = Rectangle(10, 10, 30, 30)
r2 = Rectangle(20, 20, 50, 50)

# get the union of two rectangles
union_rectangle = r1.union(r2)

# print the coordinates of the union rectangle
print('Union Rectangle:', union_rectangle.top, union_rectangle.left, union_rectangle.bottom, union_rectangle.right)
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