First attempt at ripping out agnostic code into ifcopenshell.api namespace. See #1399.

src/ifcopenshell-python/ifcopenshell/api/project/create_file.py

@@ -0,0 +1,25 @@
+import datetime
+import ifcopenshell
+
+
+class Usecase:
+    def __init__(self, settings=None):
+        self.settings = {"version": "IFC4"}
+        for key, value in settings.items():
+            self.settings[key] = value
+
+    def execute(self):
+        self.file = ifcopenshell.file(schema=self.settings["version"])
+        # TODO: add all metadata, pending bug #747
+        self.file.wrapped_data.header.file_name.name = "/dev/null"  # Hehehe
+        self.file.wrapped_data.header.file_name.time_stamp = (
+            datetime.datetime.utcnow()
+            .replace(tzinfo=datetime.timezone.utc)
+            .astimezone()
+            .replace(microsecond=0)
+            .isoformat()
+        )
+        self.file.wrapped_data.header.file_name.preprocessor_version = "IfcOpenShell {}".format(ifcopenshell.version)
+        self.file.wrapped_data.header.file_name.originating_system = "IfcOpenShell {}".format(ifcopenshell.version)
+        self.file.wrapped_data.header.file_name.authorization = "Nobody"
+        return self.file