Task: Define clean$\_$record as follows:

Clean a $($non$-$raw$)$ dictionary record.

Input: record $-$ A python dictionary as might be produced by get$\_$record

Return: cleaned $-$ A copy of record cleaned as explained below, or None if any required keys are missing.

Requirements$/$steps: The goal of this task is two$-$fold: $1)$ Ensure that the record has certain "mandatory" attributes, and $2)$ simplify the values for certain single$-$value attributes. More specifically, your function should satisfy these requirements.

$*)$If the input is missing any of the following keys, return None:$[\text{'}$id$\text{'},$ 'title', 'year', 'venue', 'abstract'$].$

$*)$For the $\text{'}$id$\text{'}$ and 'year' keys, assume there is only one value in the list and convert it into an integer and store this value.

$*)$if there is a 'refs' key, convert each element of its list to an integer and store this list of integers

$*)$For any other keys that are present in record, assume there is only one value and store that value as$-$is $($i$.$e$.,$ as a string$).$

Return the cleaned dictionary.

Example: A correct implementation should produce, for the deml, the following output:

None

$\{\text{'}$abstract$\text{'}$: 'A mathematical model for communicating sequential processes $\text{'}$

$\text{'}$is given, and a number of its interesting and useful prroperties $\text{'}$

'arestated and proved. The possibilities of nondetermimsm are $\text{'}$

'fullytaken into account.$\text{'},$

'authors': $\text{'}$S$.$D$,$Brookes, C$.$A$.$R$,$Hoare, A$.$W$.$ Roscoe',

$\text{'}$id$\text{'}$: $319,$

'refs': $[213500.318212,555632],$

'title': 'A theory of comm sequential processes',

'venue': 'Journal of the ACM $($JACM$)\text{'},$

'year': $1984\}$

code:

def clean$\_$record$($record: dict$)->$ dict:

####your code###

pprint$($clean$\_$record$($records$[0]))$ #None!

pprint$($clean$\_$record$($records$[17]))$ #valid