[USER (data scientist)]: I've got this dataset called "high_credit_long_duration" and I need to find clients with multiple existing credits and high installment commitments. We also assume that `high` installment commitments are those above the `median` value of the 'installment_commitment' column. Can you help me out? Please generate a DataFrame of clients with multiple existing credits and higher than median installment commitments.
My template of code snippet is:

---BEGIN CODE TEMPLATE---

import pandas as pd 
import pickle
 
# Load the dataset 
credit_customers = pd.read_csv("credit_customers.csv") 
 
# YOUR SOLUTION BEGIN:
<code1>
[COMPLETE YOUR CODE]
</code1>
# YOUR SOLUTION END

print(f"multiple_credits_high_commitment: {multiple_credits_high_commitment}") 

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

---END CODE TEMPLATE---

[YOU (AI assistant)]: Sure! You can use the following code to find clients with multiple existing credits and high installment commitments:
'''
import pandas as pd 
import pickle
 
# Load the dataset 
credit_customers = pd.read_csv("credit_customers.csv") 
 
# YOUR SOLUTION BEGIN:
