{"ast_node_type":"other","tokens":[{"end":38,"kind":"keyword","start":0,"text":"///"}]}
/// of 2, or this function will panic.
/// Formats a power of two as an exponent of two, i.e. 16 => ⁴. Note that `num` MUST be a power
fn pwr2_to_exponent(num: u128) -> String {