pub trait StrAssertions<T>{
// Required methods
fn contains(&self, expected: &str);
fn starts_with(&self, expected_start: &str);
fn ends_with(&self, expected_end: &str);
fn is_empty(&self);
fn is_not_empty(&self);
fn has_length(&self, expected_length: usize);
fn contains_all(&self, args: &[&str]);
fn contains_any(&self, args: &[&str]);
}