more python2 -> python3

Author: tony-sappe

date_utils/calendar_util.py

@@ -12,7 +12,7 @@
 #    The essential reference for computational positional astronomy.
 #
 
-from .astro import *
+from astro import *
 
 
 J0000 = 1721424.5  # Julian date of Gregorian epoch: 0000-01-01
@@ -111,6 +111,10 @@
 )
 
 
+def apply(func, args, kwargs=None):
+    return func(*args) if kwargs is None else func(*args, **kwargs)
+
+
 def leap_gregorian(year):
     return year % 4 == 0 and not ((year % 100) == 0 and (year % 400) != 0)