py3: introducing __round__ methods as alias for existing .round

src/sage/rings/number_field/number_field_element.pyx

@@ -1275,6 +1275,8 @@ cdef class NumberFieldElement(FieldElement):
 
         return (self + QQ((1,2))).floor()
 
+    __round__ = round
+
     def abs(self, prec=None, i=None):
         r"""Return the absolute value of this element.
 

src/sage/rings/number_field/number_field_element_quadratic.pyx

@@ -2274,7 +2274,7 @@ cdef class NumberFieldElement_quadratic(NumberFieldElement_absolute):
 
     def round(self):
         r"""
-        Returns the round (nearest integer).
+        Return the round (nearest integer).
 
         EXAMPLES::
 
@@ -2314,6 +2314,9 @@ cdef class NumberFieldElement_quadratic(NumberFieldElement_absolute):
         else:
             return n
 
+    __round__ = round
+
+
 cdef class OrderElement_quadratic(NumberFieldElement_quadratic):
     """
     Element of an order in a quadratic field.

src/sage/rings/qqbar.py

@@ -4748,6 +4748,8 @@ def round(self):
         """
         return self._floor_ceil(lambda x: x.round())
 
+    __round__ = round
+
     def trunc(self):
         r"""
         Round ``self`` to the nearest integer toward zero.

src/sage/rings/real_double.pyx

@@ -1463,6 +1463,8 @@ cdef class RealDoubleElement(FieldElement):
         """
         return Integer(round(self._value))
 
+    __round__ = round
+
     def floor(self):
         """
         Return the floor of ``self``.

src/sage/rings/real_mpfi.pyx

@@ -2997,6 +2997,8 @@ cdef class RealIntervalFieldElement(RingElement):
         """
         return self.parent()(self.lower().round(), self.upper().round())
 
+    __round__ = round
+
     def trunc(self):
         r"""
         Return the truncation of this interval as an interval

src/sage/rings/real_mpfr.pyx

@@ -2839,6 +2839,8 @@ cdef class RealNumber(sage.structure.element.RingElement):
         mpfr_round(x.value, self.value)
         return x.integer_part()
 
+    __round__ = round
+
     def floor(self):
         """
         Return the floor of ``self``.

src/sage/symbolic/expression.pyx

@@ -6025,6 +6025,8 @@ cdef class Expression(CommutativeRingElement):
         else:
             return result
 
+    __round__ = round
+
     def function(self, *args):
         """
         Return a callable symbolic expression with the given variables.