feeds: centralize time format/parse

At the same code _should_ apply to most, if not all, parsers

morss/feeds.py

@@ -188,10 +188,17 @@ class ParserBase(object):
 
     def time_prs(self, x):
         # parse
-        pass
+        try:
+            return parse_time(x)
+        except ValueError:
+            return None
 
     def time_fmt(self, x):
         # format
+        try:
+            time = parse_time(x)
+            return time.strftime(self.rules['timeformat'])
+        except ValueError:
             pass
 
     def get_raw(self, rule_name):
@@ -351,19 +358,6 @@ class ParserXML(ParserBase):
     def bool_fmt(self, x):
         return 'true' if x else 'false'
 
-    def time_prs(self, x):
-        try:
-            return parse_time(x)
-        except ValueError:
-            return None
-
-    def time_fmt(self, x):
-        try:
-            time = parse_time(x)
-            return time.strftime(self.rules['timeformat'])
-        except ValueError:
-            pass
-
     def get_raw(self, rule_name):
         return self.rule_search_all(self.rules[rule_name])