Return support for creating uninitialized files from Python

Created a new method to avoid complicating `ifcopenshell.file` ctor signature.

src/ifcwrap/IfcParseWrapper.i

@@ -260,6 +260,7 @@ private:
 %}
 
 %newobject ifcopenshell::file::key_value_store_iter;
+%newobject ifcopenshell::file::create_uninitialized;
 
 %extend ifcopenshell::file {
 	/*
@@ -274,6 +275,10 @@ private:
 		return new ifcopenshell::file(ifcopenshell::schema_by_name(schema));
 	}
 
+	static ifcopenshell::file* create_uninitialized(logger* logger=nullptr) {
+		return new ifcopenshell::file(ifcopenshell::uninitialized_tag{}, logger_or_root(logger));
+	}
+
 	std::vector<express::Base> _get_inverse(const express::Base& e) {
 		if (auto e_ = e.as<express::Entity>()) {
 			return cast_vector<express::Base>($self->get_inverse(e_.id(), 0, -1));