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Fixes #1955

util/timedeltastring.py

@@ -0,0 +1,41 @@
+from datetime import timedelta
+
+def convert_to_timedelta(time_val):
+  """
+  From: code.activestate.com/recipes/577894-convert-strings-like-5d-and-60s-to-timedelta-objec
+
+  Given a *time_val* (string) such as '5d', returns a timedelta object
+  representing the given value (e.g. timedelta(days=5)).  Accepts the
+  following '<num><char>' formats:
+
+  =========   ======= ===================
+  Character   Meaning Example
+  =========   ======= ===================
+  s           Seconds '60s' -> 60 Seconds
+  m           Minutes '5m'  -> 5 Minutes
+  h           Hours   '24h' -> 24 Hours
+  d           Days    '7d'  -> 7 Days
+  =========   ======= ===================
+
+  Examples::
+
+      >>> convert_to_timedelta('7d')
+      datetime.timedelta(7)
+      >>> convert_to_timedelta('24h')
+      datetime.timedelta(1)
+      >>> convert_to_timedelta('60m')
+      datetime.timedelta(0, 3600)
+      >>> convert_to_timedelta('120s')
+      datetime.timedelta(0, 120)
+  """
+  num = int(time_val[:-1])
+  if time_val.endswith('s'):
+    return timedelta(seconds=num)
+  elif time_val.endswith('m'):
+    return timedelta(minutes=num)
+  elif time_val.endswith('h'):
+    return timedelta(hours=num)
+  elif time_val.endswith('d'):
+    return timedelta(days=num)
+  else:
+    raise ValueError('Unknown suffix on timedelta: %s' % time_val)