Question $2$

Merge flights$\_$df dataframe with airports$\_$df dataframe and return the number of departing flights $($NUM$\_$FLIGHTS$)$ per airport $($IATA$\_$CODE$)$ across the year.

$[4]$:

import pandas as pd

def flights$\_$per$\_$airport$($flights$\_$df$,$ airports$\_$df$)$:

num$\_$flights$\_$df$=$flights$\_$df$.$merge$($airports$\_$df$,$ left$\_$on$=$'ORIGIN$\_$AIRPORT $\text{'},$ right$\_$on$=$'IATA$\_$CODE', how$=\text{'}$ left' $)$

num$\_$flights$\_$df$=$flights$\_$df$.$groupby$([\text{'}$IATA$\_$CODE'$])[\text{'}$FLIGHT$\_$NUMBER'$].$count $().$reset$\_$index$()$

num$\_$flights$\_$df$.$ rename $($columns$=\{\text{'}$FLIGHT$\_$NUMBER' : 'NUM$\_$FLIGHTS'$\},$ inplace$=$True$)$

num$\_$flights$\_$df$.$drop$($columns$=[\text{'}$IATA$\_$CODE'$],$ inplace$=$True$)$

return num$\_$flights$\_$df

flights$\_$df$\_$raw $=$ pd$.$read$\_$csv$(\text{'}$assets$/$flights$.$csv$\text{'},$ low$\_$memory$=$False$)$

airports$\_$df $=$ pd$.$read$\_$csv$(\text{'}$assets$/$airports$.$csv$\text{'})$

num$\_$flights$\_$df $=$ flights$\_$per$\_$airport$($flights$\_$df$\_$raw.copy$(),$ airports$\_$df$.$copy$())$

print$($num$\_$flights$\_$df$)$

Key error 'IATA$\_$CODE'

How do i fix?