runtime error handling

src/videos.rs

@@ -431,6 +431,13 @@ impl VideoFormat {
         }
         self.to_owned()
     }
+    pub fn http_headers_pairs(&self) -> Vec<(String, String)> {
+        self.http_headers
+            .clone()
+            .unwrap_or_default()
+            .into_iter()
+            .collect()
+    }
     pub fn format_id(mut self, format_id: String) -> Self {
         self.format_id = Some(format_id);
         self