"• Drop rows for the columns (AH, MAV, CD) where at least one row value is NULL." code example

Example 1: remove rows or columns with NaN value

df.dropna()     #drop all rows that have any NaN values
df.dropna(how='all')

Example 2: remove all rows where one ccolumns egale to nan

#remove in dataframe but no in the file
df = df[df['column'].notna()]

#remove in dataframe and in the file
df.dropna(subset=['EPS'], how='all', inplace=True)