pd.DataFrame(X).fillna() code example

Example 1: fillna with mean pandas

sub2['income'].fillna((sub2['income'].mean()), inplace=True)

Example 2: python pandas fillna

# importing pandas module
import pandas as pd  
# making data frame from csv file
nba = pd.read_csv("nba.csv")
  
# replacing na values in college with No college
nba["College"].fillna("No College", inplace = True)
# OR
nba.College.fillna("No College", inplace = True)
  
print(nba)