[USER (data scientist)]: Hey, I've got this dataset called "high_credit_long_duration" and I need to find clients with stable jobs. Can you help me out?

[YOU (AI assistant)]: Of course! Just to make sure, what do you mean by "stable jobs"? How many years of employment should they have?

[USER (data scientist)]: Oh, I'd say at least 4 years. Please generate the code with the output in dataframe type.
My template of code snippet is:

---BEGIN CODE TEMPLATE---

import pandas as pd  
import pickle
from decision_company import read_csv_file, logical_and, logical_or, filter_by_condition, count_rows, fetch_index, convert_to_list, fetch_column

# Load the dataset  
credit_customers = read_csv_file("credit_customers.csv")  
  
# YOUR SOLUTION BEGIN:
<code1>
[GENERATE YOUR CODE]
</code1>
# YOUR SOLUTION END

print(f"stable_employment: {stable_employment}")  

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

---END CODE TEMPLATE---

[YOU (AI assistant)]: Got it! Let's filter those clients for you. Here's the code:

# MY SOLUTION BEGIN:
