Implement metric constraints in the ifcopenshell.api

src/ifcopenshell-python/ifcopenshell/api/constraint/add_metric.py

@@ -0,0 +1,21 @@
+import ifcopenshell
+
+class Usecase:
+    def __init__(self, file, **settings):
+        self.file = file
+        self.settings = {
+            "objective": None,
+        }
+        for key, value in settings.items():
+            self.settings[key] = value
+
+    def execute(self):
+        metric = self.file.create_entity("IfcMetric", **{
+            "Name": "Unnamed",
+            "ConstraintGrade": "NOTDEFINED",
+            "Benchmark": "EQUALTO",
+        })
+        if self.settings["objective"]:
+            benchmark_values = list(self.settings["objective"].BenchmarkValues or [])
+            benchmark_values.append(metric)
+        return metric