Make a module `pub(crate)` rather than `pub`
@@ -13,9 +13,10 @@ use crate::{PreparedBlock, ValidateContextError};
use super::check;
-pub mod difficulty;
use difficulty::{AdjustedDifficulty, POW_MEDIAN_BLOCK_SPAN};
+pub(crate) mod difficulty;
+
/// Check that `block` is contextually valid for `network`, based on the
/// `finalized_tip_height` and `relevant_chain`.
///
