Computer program contains everything that's secret in General Election (6)
I believe the answer is:
ballot
'that's secret in general election' is the definition.
'computer program contains everything' is the wordplay.
'computer program' becomes 'bot'.
'contains' is an insertion indicator.
'everything' becomes 'all' (I've seen this before).
'bot' placed around 'all' is 'BALLOT'.
(Other definitions for ballot that I've seen before include "Vote or suffrage" , "Voting procedure" , "Lottery to allocate (tickets) among applicants" , "The process of voting" , "Secret vote" .)