diff --git a/2-7-diy2.py b/2-7-diy2.py
new file mode 100644
index 0000000..fc56004
--- /dev/null
+++ b/2-7-diy2.py
@@ -0,0 +1,5 @@
+# 需要进行加密的语句
+message = "诺依，周末一起去看动漫展吧！"
+# 请对message进行遍历，取出所有元素
+for i in message:
+    print(i)
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diff --git a/2-7-diy4.py b/2-7-diy4.py
new file mode 100644
index 0000000..9ef678e
--- /dev/null
+++ b/2-7-diy4.py
@@ -0,0 +1,16 @@
+import random
+# 私钥
+key = "abcdefgh使用编程实现位移替换加密，制作密码机关真是太好玩了哈哈！"
+# 要加密语句
+message = "诺依，周末一起去看动漫展吧！"
+# 加密后的语句(密文)
+key_message = ""
+
+# 加密过程
+for i in message:
+    str1 = i
+    str2 = random.choice(key)
+    str3 = random.choice(key)
+    text = str1+str2+str3
+    key_message = key_message + text
+print(key_message)
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