multiline docstring handling

Author: parikshit14

examples/document.py

@@ -21,7 +21,8 @@ class Paragraph(Base):
 @modelspec.define
 class Section(Base):
     """
-    A model of a section of the :class:`Document`. Will contain one :class:`Paragraph` or more
+    A model of a section of the :class:`Document`.
+    Will contain one :class:`Paragraph` or more.
 
     Args:
         id: The id of the section

src/modelspec/base_types.py

@@ -373,7 +373,11 @@ def _parse_definition(cls) -> str:
         p = parse(cls.__doc__)
 
         # Extract the description, use the long description if available.
-        return p.long_description if p.long_description else p.short_description
+        if p.long_description:
+            definition = p.short_description + p.long_description
+        else:
+            definition = p.short_description
+        return definition
 
     @classmethod
     def _parse_allowed_fields(cls) -> Dict[str, Tuple[str, Any]]: