XEP-0082: Move from mini_dateutil to datetime

Since datetime got merged into Python (probably around py3k), it’s now
usable for all of our needs and so we can do away with the old fallback.

slixmpp/plugins/xep_0082.py

@@ -6,7 +6,6 @@
 import datetime as dt
 
 from slixmpp.plugins import BasePlugin, register_plugin
-from slixmpp.thirdparty import tzutc, tzoffset, parse_iso
 
 
 # =====================================================================
@@ -21,7 +20,10 @@ def parse(time_str):
     Arguments:
         time_str -- A formatted timestamp string.
     """
-    return parse_iso(time_str)
+    try:
+        return dt.datetime.strptime(time_str, '%Y-%m-%dT%H:%M:%S.%f%z')
+    except ValueError:
+        return dt.datetime.strptime(time_str, '%Y-%m-%dT%H:%M:%S%z')
 
 
 def format_date(time_obj):
@@ -52,7 +54,7 @@ def format_time(time_obj):
     if isinstance(time_obj, dt.datetime):
         time_obj = time_obj.timetz()
     timestamp = time_obj.isoformat()
-    if time_obj.tzinfo == tzutc():
+    if time_obj.tzinfo == dt.timezone.utc:
         timestamp = timestamp[:-6]
         return '%sZ' % timestamp
     return timestamp
@@ -69,7 +71,7 @@ def format_datetime(time_obj):
         time_obj -- A datetime object.
     """
     timestamp = time_obj.isoformat('T')
-    if time_obj.tzinfo == tzutc():
+    if time_obj.tzinfo == dt.timezone.utc:
         timestamp = timestamp[:-6]
         return '%sZ' % timestamp
     return timestamp
@@ -128,9 +130,9 @@ def time(hour=None, min=None, sec=None, micro=None, offset=None, obj=False):
     if micro is None:
         micro = now.microsecond
     if offset in (None, 0):
-        offset = tzutc()
+        offset = dt.timezone.utc
     elif not isinstance(offset, dt.tzinfo):
-        offset = tzoffset(None, offset)
+        offset = dt.timezone(dt.timedelta(seconds=offset))
     value = dt.time(hour, min, sec, micro, offset)
     if obj:
         return value
@@ -175,9 +177,9 @@ def datetime(year=None, month=None, day=None, hour=None,
     if micro is None:
         micro = now.microsecond
     if offset in (None, 0):
-        offset = tzutc()
+        offset = dt.timezone.utc
     elif not isinstance(offset, dt.tzinfo):
-        offset = tzoffset(None, offset)
+        offset = dt.timezone(dt.timedelta(seconds=offset))
 
     value = dt.datetime(year, month, day, hour,
                        min, sec, micro, offset)