AttributeError: 'DataFrame' object has no attribute 'unique'

AttributeError: 'DataFrame' object has no attribute 'unique'

The error message "'DataFrame' object has no attribute 'unique'" occurs when you are trying to use the unique() method on a pandas DataFrame object, but this method is only available for pandas Series objects.

#1. Applying unique to dataframe

df = pd.DataFrame([{"A":"aaa","B":"bbb"}])

print(df.unique()) #Throws error

#2. Error can be reproduced if dataframe has multiple columns with same name.The error can pop-up if column is renamed mistakenly.

import pandas as pd

df = pd.DataFrame([{"A":"aaa","B":"bbb"}])

print(df)

print(df['A'].dropna().unique()) #works fine

df =df.rename(columns={ df.columns[1]:df.columns[0] }) # column

print(df)

print(df['A'].dropna().unique()) #

Hope it helps!!