PEP 751: Fix example (#4256)

Author: brettcannon

peps/pep-0751.rst

@@ -154,20 +154,6 @@ consistent order. Usage of inline tables SHOULD also be kept consistent.
 - If an tool doesn't support a major version, it MUST raise an error.
 
 
-``created-by``
-==============
-
-- **Type**: string
-- **Required?**: yes
-- **Inspiration**: Tools with their name in their lock file name
-- Records the name of the tool used to create the lock file.
-- Tools MAY use the ``[tool]`` table to record enough details that it can be
-  inferred what inputs were used to create the lock file.
-- Tools SHOULD record the normalized name of the tool if it is available as a
-  Python package to facilitate finding the tool.
-
-
-
 ``environments``
 ================
 
@@ -202,6 +188,19 @@ consistent order. Usage of inline tables SHOULD also be kept consistent.
   be installed MUST narrow down to a single entry at install time.
 
 
+``created-by``
+==============
+
+- **Type**: string
+- **Required?**: yes
+- **Inspiration**: Tools with their name in their lock file name
+- Records the name of the tool used to create the lock file.
+- Tools MAY use the ``[tool]`` table to record enough details that it can be
+  inferred what inputs were used to create the lock file.
+- Tools SHOULD record the normalized name of the tool if it is available as a
+  Python package to facilitate finding the tool.
+
+
 .. Identification
 
 ``packages.name``
@@ -647,6 +646,7 @@ Example
 
   metadata-version = "1.0"
   requires-python = ">=3.9"
+  created-by = "PEP 751"
 
   [[packages]]
   name = "attrs"