[FIX] output management cleanups (#464)

* return on \n before empty div is appended

* use appendOutput with out.write

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

Co-authored-by: Mariano Weber <info@uiremotely.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

pyscriptjs/src/pyscript.py

@@ -153,6 +153,10 @@ class Element:
 
         out_element_id = self.id
 
+        html, mime_type = format_mime(value)
+        if html == "\n":
+            return
+
         if append:
             child = document.createElement("div")
             exec_id = self.element.childElementCount + 1
@@ -161,13 +165,10 @@ class Element:
 
         out_element = document.querySelector(f"#{out_element_id}")
 
-        html, mime_type = format_mime(value)
         if mime_type in ("application/javascript", "text/html"):
             script_element = document.createRange().createContextualFragment(html)
             out_element.appendChild(script_element)
         else:
-            if html == "\n":
-                return
             out_element.innerHTML = html
 
     def clear(self):