I have a dataframe, 

```
       plan_identifier wellthie_issuer_identifier
0  UNM99901AL0000001-DEN                   UNM99902
1  UNM99902AK0000001-DEN                   UNM99902
2  UNM99904AZ0000001-DEN                   UNM99904
3  UNM99905AR0000001-DEN                   UNM99905
4  UNM99906CA0000001-DEN                   UNM99906
5  UNM99908CO0000001-DEN                   UNM99909
6  UNM99909CT0000001-DEN                   UNM99909

```

I need to check if the substring of `plan_identifier` considered after getting the length of `wellthie_issuer_identifier` is equal or not?

Ex- length of `UNM99902` is 8 , so my `plan_identifier` substring = `UNM99901`. Now this should return me False.

So , wherever this is not equal I should get False.

My output should be:-

```
FALSE
TRUE
TRUE
TRUE
TRUE
FALSE
TRUE

```

I tried something like below-

```
print(~(df['plan_identifier'].str[:(df['wellthie_issuer_identifier'].astype(str).str.len())] != df['wellthie_issuer_identifier']))

```

How to achieve this? Can we use apply()?