Most modules have such a blank line, but some don't. Inserting the blank line makes it clearer that the `//!` comments are describing the entire module, rather than the `use` declaration(s) that immediately follows.
Most modules have such a blank line, but some don't. Inserting the blank line makes it clearer that the `//!` comments are describing the entire module, rather than the `use` declaration(s) that immediately follows.