[USER (data scientist)]: Hey, I've got this dataset of tennis matches on grass court and I want to find out how well top 10 players perform in specific rounds of grass court tournaments. Can you give me a hand? Please generate and display a list of specific tennis match rounds.
My template of code snippet is:

---BEGIN CODE TEMPLATE---

import pandas as pd
import numpy as np
import pickle

atp_tennis = pd.read_csv('atp_tennis.csv')

# YOUR SOLUTION BEGIN:
<code1>
[COMPLETE YOUR CODE] 
</code1>
# YOUR SOLUTION END

print(rounds)

# save data
pickle.dump(rounds,open("./pred_result/rounds.pkl","wb"))

---END CODE TEMPLATE---

[YOU (AI assistant)]: Of course, happy to help! Let's start by listing the rounds in the tournament. Here's a simple way to do it:
'''
import pandas as pd
import numpy as np
import pickle

atp_tennis = pd.read_csv('atp_tennis.csv')

# YOUR SOLUTION BEGIN:
