added previous lesson info endpoint + type

src/class_book/class_book_lesson_past.rs

@@ -0,0 +1,5 @@
+pub struct ClassBookLessonPast{
+    pub lesson_id: String,
+    pub last_theme: Option<String>,
+    pub next_label: Option<String>,
+}

src/class_book/endpoints.rs

@@ -1,4 +1,4 @@
-use crate::{ClassBookSaveAbsenceRequest, ContentType, Endpoint};
+use crate::{ClassBookLessonPast, ClassBookSaveAbsenceRequest, ContentType, Endpoint};
 use std::marker::PhantomData;
 
 pub const EDIT_CLASSBOOK_ENDPOINT: Endpoint<(), ClassBookSaveAbsenceRequest> = Endpoint::Post {
@@ -7,3 +7,9 @@ pub const EDIT_CLASSBOOK_ENDPOINT: Endpoint<(), ClassBookSaveAbsenceRequest> = E
     content_type: ContentType::Json,
     _types: PhantomData,
 };
+
+pub const PREVIOUS_LESSON_INFO_CLASSBOOK_ENDPOINT: Endpoint<ClassBookLessonPast, ()> = Endpoint::Get {
+    url: "/api/3/classbook/{recordId}",
+    auth: true,
+    _types: PhantomData,
+};

src/class_book/mod.rs

@@ -1,5 +1,7 @@
 mod endpoints;
 mod class_book_save_absence_request;
+mod class_book_lesson_past;
 
 pub use class_book_save_absence_request::*;
-pub use endpoints::*;
+pub use endpoints::*;
+pub use class_book_lesson_past::*;