[Fixed] add dBW, decibel watts

CHANGES

@@ -4,6 +4,7 @@ Pint Changelog
 0.24 (unreleased)
 -----------------
 
+- Added dBW, decibel Watts, which is used in RF high power applications
 - NumPy 2.0 support
   (PR #1985, #1971)
 - Implement numpy roll (Related to issue #981)

pint/default_en.txt

@@ -504,6 +504,7 @@ refractive_index_unit = [] = RIU
 
 # Logaritmic Units of dimensionless quantity: [ https://en.wikipedia.org/wiki/Level_(logarithmic_quantity) ]
 
+decibelwatt = watt; logbase: 10; logfactor: 10 = dBW
 decibelmilliwatt = 1e-3 watt; logbase: 10; logfactor: 10 = dBm
 decibelmicrowatt = 1e-6 watt; logbase: 10; logfactor: 10 = dBu
 

pint/testsuite/test_log_units.py

@@ -65,6 +65,11 @@ def test_log_convert(self):
         helpers.assert_quantity_almost_equal(
             self.Q_(0.0, "dBm"), self.Q_(29.999999999999996, "dBu"), atol=1e-7
         )
+        # ## Test dB to dB units dBm - dBW
+        # 0 dBW = 1W = 1e3 mW = 30 dBm
+        helpers.assert_quantity_almost_equal(
+            self.Q_(0.0, "dBW"), self.Q_(29.999999999999996, "dBm"), atol=1e-7
+        )
 
     def test_mix_regular_log_units(self):
         # Test regular-logarithmic mixed definition, such as dB/km or dB/cm
@@ -84,6 +89,8 @@ def test_mix_regular_log_units(self):
 
 
 log_unit_names = [
+    "decibelwatt",
+    "dBW",
     "decibelmilliwatt",
     "dBm",
     "decibelmicrowatt",
@@ -135,6 +142,7 @@ def test_quantity_by_multiplication(module_registry_auto_offset, unit_name, mag)
 @pytest.mark.parametrize(
     "unit1,unit2",
     [
+        ("decibelwatt", "dBW"),
         ("decibelmilliwatt", "dBm"),
         ("decibelmicrowatt", "dBu"),
         ("decibel", "dB"),