pep-0426: add generator field

pep-0426.txt

@@ -415,6 +415,7 @@ The essential dependency resolution metadata consists of the following
 fields:
 
 * ``metadata_version``
+* ``generator``
 * ``name``
 * ``version``
 * ``source_label``
@@ -502,6 +503,17 @@ Example::
     "metadata_version": "2.0"
 
 
+Generator
+---------
+
+Name (and optional version) of the program that generated the file,
+if any.  A manually produced file would omit this field.
+
+Example::
+
+    "generator": "setuptools (0.8)"
+
+
 Name
 ----
 

pep-0426/pymeta-schema.json

@@ -9,6 +9,11 @@
       "type": "string",
       "pattern": "^(\\d+(\\.\\d+)*)$"
     },
+    "generator": {
+      "description": "Name and version of the program that produced this file.",
+      "type": "string",
+      "pattern": "^[0-9A-Za-z]([0-9A-Za-z_.-]*[0-9A-Za-z])( \\((\\d+(\\.\\d+)*)((a|b|c|rc)(\\d+))?(\\.(post)(\\d+))?(\\.(dev)(\\d+))\\))?$"
+    },
     "name": {
       "description": "The name of the distribution.",
       "type": "string",