How to find probability without replacement using only pandas and random?

The simulation has square as both shape1 and shape2 but it shouldn't happen if we run without replacement. I know the code runs well but I don't know how to solve this situation.

import pandas as pd
import random

creating the simulation

def simulation1():
    shape1 = random.choice(["square", "pentagon", "octagon"])
    return shape1
def simulation2():
    shape2 = random.choice(["square", "pentagon", "octagon"])
    return shape2

storing the simulation as a dataframe

data = []
for i in range(1000):
    d = {"shape1": simulation1(), "shape2": simulation2()}
    data.append(d)
    
df = pd.DataFrame(data)