Imagine we create a pandas series using the below code. What is one simple way to retrieve the value $0\mathrm{.}5$ from the series?

import pandas as pd

$df=$ pd$.$Series $0\mathrm{.}75,0\mathrm{.}25,1\mathrm{.}00,\mathrm{.}50,$

index $\text{'},[$:$f^{\text{'}}{b}^{\text{'}},{|}^{\text{'}}{c}^{\text{'}},{|}^{\text{'}}{d}^{\text{'}}\}$

df

df $[\text{'}$ loc

$df[c^{\text{'}}]$

df$[\text{'}$b$\text{'}]$

df$.$find $\mathrm{.}50$

iff'd$]$

dfliloc$-5?$

df $[\text{'}$a$\text{'}$i$\text{'}]$