diff --git a/4.21.py b/4.21.py
new file mode 100644
index 0000000..6b1e69a
--- /dev/null
+++ b/4.21.py
@@ -0,0 +1,6 @@
+text = "hello"
+for char in text:
+    print(f"'{char}'的ASCII码是:{ord(char)}")
+
+character_A = chr(65)
+print(character_A)
\ No newline at end of file