A tiny edit

Author: kwankyu

src/doc/en/developer/coding_in_python.rst

@@ -477,7 +477,7 @@ A method or a function accepts input described in the ``INPUT`` block of
 :ref:`the docstring <section-docstring-function>` and returns output. If the
 input cannot be handled by the code, then it may raise an exception.  The
 following aims to guide you in choosing from the most relevant exceptions to
-Sage:
+Sage. Raise
 
 - `TypeError <https://docs.python.org/3/library/exceptions.html#TypeError>`_:
   if the input belongs to a class of objects that are not supported by the