headers abstract method

TRes headers(
  1. Iterable<Query$getUpcomingChallengesByTargetAndUserAudiencePaginated$getUpcomingChallengesByTargetAndUserAudiencePaginated$objects$donation$donation$donation$cause$coin$api$deduct$headers>? _fn(
    1. Iterable<CopyWith$Query$getUpcomingChallengesByTargetAndUserAudiencePaginated$getUpcomingChallengesByTargetAndUserAudiencePaginated$objects$donation$donation$donation$cause$coin$api$deduct$headers<Query$getUpcomingChallengesByTargetAndUserAudiencePaginated$getUpcomingChallengesByTargetAndUserAudiencePaginated$objects$donation$donation$donation$cause$coin$api$deduct$headers>>?
    )
)

Implementation

TRes headers(
    Iterable<Query$getUpcomingChallengesByTargetAndUserAudiencePaginated$getUpcomingChallengesByTargetAndUserAudiencePaginated$objects$donation$donation$donation$cause$coin$api$deduct$headers>? Function(
            Iterable<
                CopyWith$Query$getUpcomingChallengesByTargetAndUserAudiencePaginated$getUpcomingChallengesByTargetAndUserAudiencePaginated$objects$donation$donation$donation$cause$coin$api$deduct$headers<
                    Query$getUpcomingChallengesByTargetAndUserAudiencePaginated$getUpcomingChallengesByTargetAndUserAudiencePaginated$objects$donation$donation$donation$cause$coin$api$deduct$headers>>?)
        _fn);