Update PythonRuntimeTests.swift

Author: philipturner

Tests/PythonKitTests/PythonRuntimeTests.swift

@@ -20,6 +20,10 @@ class PythonRuntimeTests: XCTestCase {
         XCTAssertEqual(1.5, polymorphicList[3])
         XCTAssertEqual(1.5, polymorphicList[-1])
 
+        XCTAssertEqual(4, polymorphicList.count)
+        XCTAssertEqual(4, polymorphicList.checking.count!)
+        XCTAssertEqual(4, polymorphicList.throwing.count!)
+        
         polymorphicList[2] = 2
         XCTAssertEqual(2, polymorphicList[2])
     }
@@ -30,6 +34,10 @@ class PythonRuntimeTests: XCTestCase {
         XCTAssertEqual(2, Python.len(dict))
         XCTAssertEqual(1, dict["a"])
         XCTAssertEqual(0.5, dict[1])
+      
+        XCTAssertEqual(2, polymorphicList.count)
+        XCTAssertEqual(2, polymorphicList.checking.count!)
+        XCTAssertEqual(2, polymorphicList.throwing.count!)
 
         dict["b"] = "c"
         XCTAssertEqual("c", dict["b"])