please modify the following python code to fix the logic errors: from datetime import datetime

def calculate$\_$duration$($date$\_$str$)$:

try:

input$\_$date $=$ datetime.strptime$($date$\_$str$,\text{'}\%$m$/\%$d$/\%$Y$\text{'})$

except ValueError:

return "Invalid date format. Please enter date in MM$/$DD$/$YYYY format."

current$\_$date $=$ datetime.now$()$

duration $=$ current$\_$date $-$ input$\_$date

years $=$ duration.days $//365$

months $=($duration$.$days $\%365)//30$

weeks $=($duration$.$days $\%365)\%30//7$

days $=($duration$.$days $\%365)\%30\%7$

result $=$ f$"\{$years$\}$ years, $\{$months$\}$ months, $\{$weeks$\}$ weeks, and $\{$days$\}$ days ago."

return result

date$\_$input $=$ input$("$Enter a date $($MM$/$DD$/$YYYY$)$: $")$

print$($calculate$\_$duration$($date$\_$input$))$