Update to reflect the equivalence:

Decimal(12345)==Decimal('12345') where the precision is three

pep-0327.txt

@@ -728,10 +728,13 @@ So, here I define the behaviour again for each data type.
 From int or long
 ''''''''''''''''
 
-Aahz suggested the need of an explicit conversion from int, but also
-thinks it's OK if the precision in the current Context is not
-exceeded; in that case you raise ValueError.  Votes in
-comp.lang.python agreed with this.
+An int or long is a treated like a Decimal explicitly constructed from
+Decimal(str(x)) in the current context (meaning that the to-string rules
+for rounding are applied and the appropriate flags are set).  This
+guarantees that expressions like ``Decimal('1234567') + 13579`` match
+the mental model of ``Decimal('1234567') + Decimal('13579')``.  That
+model works because all integers are representable as strings without
+representation error.
 
 
 From string