updated the organic name when creating the object

measurement/base.py

@@ -5,6 +5,7 @@
 import inspect
 import warnings
 from functools import total_ordering
+from math import floor, log10
 from typing import Any, Dict, Iterable, List, Optional, Tuple, Type, Union
 
 
@@ -257,6 +258,22 @@ def __init__(
         self.unit = self._units[unit]
         self.unit.org_name = unit
         self.si_value = self.unit.to_si(value)
+        self.units_conversor = self.units_conversor = {
+            float(v.factor): k for k, v in self._units.items() if len(k) <= 3
+        }
+        self.update_org_name()
+
+    def update_org_name(self):
+        if self.si_value == 0:
+            self.unit.org_name = self.units_conversor[1.0]
+        else:
+            factor = float(10 ** int((floor(log10(self.si_value) / 3) * 3)))
+            if factor in self.units_conversor:
+                self.unit.org_name = self.units_conversor[factor]
+            elif factor > max(self.units_conversor):
+                self.unit.org_name = self.units_conversor[max(self.units_conversor)]
+            elif factor < min(self.units_conversor):
+                self.unit.org_name = self.units_conversor[min(self.units_conversor)]
 
     def __getattr__(self, name):
         try:

tests/test_base.py

@@ -79,6 +79,9 @@ class TestAbstractMeasure:
     measure = Distance
     unit = "m"
 
+    def test_update_org_name(self):
+        assert str(Distance("0.001 m")) == "1 mm"
+
     def test_repr(self):
         assert repr(Distance("1 km")) == 'Distance(metre="1E+3")'