Use 'floor' rather than 'rint', just in case there are platforms that…

… have floor but not rint
python · mdickinson · Aug 17, 2021 · Aug 15, 2021 · Aug 15, 2021 · Aug 15, 2021
commit c03c9a5aaaa7b61868a0f833c195aae07191f548
diff --git a/Objects/complexobject.c b/Objects/complexobject.c
@@ -518,7 +518,7 @@ complex_pow(PyObject *v, PyObject *w, PyObject *z)
     }
     errno = 0;
     exponent = b;
-    if (exponent.imag == 0.0 && exponent.real == rint(exponent.real)
+    if (exponent.imag == 0.0 && exponent.real == floor(exponent.real)
                              && fabs(exponent.real) <= 100.0) {
         p = c_powi(a, (long)exponent.real);
     }