I'd like to get a unique of a series of a dataframe while preserving its index

I’d like to get a unique of a series of a dataframe while preserving its index:

In Particular i have an datframe with two columns:’Stock’ and ‘Company Name’.

I’m using the follow code:

lot = titoli1['Stock'].unique()

but the returns is a unique serie but i want both series value related on unique, stock, value.

Thank you in advance for youre time spented!

>Solution :

I guess you are looking for this,

df[~df['col'].duplicated(keep='first')]

Sample Input:

   col
0    1
1    2
2    3
3    1
4    2

Sample Output:

   col
0    1
1    2
2    3