Function aws_smithy_json::deserialize::token::expect_timestamp_or_null

pub fn expect_timestamp_or_null(
    token: Option<Result<Token<'_>, Error>>, 
    timestamp_format: Format
) -> Result<Option<Instant>, Error>

Expects a Token::ValueNull, Token::ValueString, or Token::ValueNumber depending on the passed in timestamp_format. If there is a non-null value, it interprets it as an Instant in the requested format.