1 files changed, 29 insertions, 0 deletions
diff --git a/Lib/string.py b/Lib/string.py
index 261789c..2eab6d4 100644
--- a/Lib/string.py
+++ b/Lib/string.py
@@ -141,6 +141,35 @@ class Template:
                              self.pattern)
         return self.pattern.sub(convert, self.template)
 
+    def is_valid(self):
+        for mo in self.pattern.finditer(self.template):
+            if mo.group('invalid') is not None:
+                return False
+            if (mo.group('named') is None
+                and mo.group('braced') is None
+                and mo.group('escaped') is None):
+                # If all the groups are None, there must be
+                # another group we're not expecting
+                raise ValueError('Unrecognized named group in pattern',
+                    self.pattern)
+        return True
+
+    def get_identifiers(self):
+        ids = []
+        for mo in self.pattern.finditer(self.template):
+            named = mo.group('named') or mo.group('braced')
+            if named is not None and named not in ids:
+                # add a named group only the first time it appears
+                ids.append(named)
+            elif (named is None
+                and mo.group('invalid') is None
+                and mo.group('escaped') is None):
+                # If all the groups are None, there must be
+                # another group we're not expecting
+                raise ValueError('Unrecognized named group in pattern',
+                    self.pattern)
+        return ids
+
 # Initialize Template.pattern.  __init_subclass__() is automatically called
 # only for subclasses, not for the Template class itself.
 Template.__init_subclass__()