diff --git a/04-CustomLibrary/ipandstring/__init__.py b/04-CustomLibrary/ipandstring/__init__.py
new file mode 100644
index 0000000..e7adf5c
--- /dev/null
+++ b/04-CustomLibrary/ipandstring/__init__.py
@@ -0,0 +1,4 @@
+from ipandstring.stringip import stringandip
+
+class ipandstring(stringandip): 
+     ROBOT_LIBRARY_SCOPE = 'GLOBAL'
\ No newline at end of file
diff --git a/04-CustomLibrary/ipandstring/stringip.py b/04-CustomLibrary/ipandstring/stringip.py
new file mode 100644
index 0000000..9a094ba
--- /dev/null
+++ b/04-CustomLibrary/ipandstring/stringip.py
@@ -0,0 +1,68 @@
+import random
+import struct
+import socket
+
+class stringandip (object):
+    def __init__(self):
+        pass
+    def ipv4(self,m, n, x):
+        if m == '-1':
+            m = random.randint(0, 255)
+        if n == '-1':
+            n = random.randint(0, 255)
+        if x == '-1':
+            x = random.randint(0, 255)
+        y = random.randint(0, 255)
+        print(str(m) + '.' + str(n) + '.' + str(x) + '.' + str(y))
+        return str(m) + '.' + str(n) + '.' + str(x) + '.' + str(y)
+
+    def dec2hex(self,string_num):
+        base = [str(x) for x in range(10)] + [chr(x) for x in range(ord('A'), ord('A') + 6)]
+        num = int(string_num)
+        mid = []
+        while True:
+            if num == 0: break
+            num, rem = divmod(num, 16)
+            mid.append(base[rem])
+
+        return ''.join([str(x) for x in mid[::-1]])
+
+    def ipv6(self):
+        ipInt = random.randint(0, 400000000000000000000000000000000000)
+        ipStr = ''
+        leftValue = ipInt
+
+        for i in [7, 6, 5, 4, 3, 2, 1, 0]:
+            string_num = leftValue / 65536 ** i
+            base = [str(x) for x in range(10)] + [chr(x) for x in range(ord('A'), ord('A') + 6)]
+            num = int(string_num)
+            mid = []
+            while True:
+                if num == 0: break
+                num, rem = divmod(num, 16)
+                mid.append(base[rem])
+
+            ipTokenInt = ''.join([str(x) for x in mid[::-1]])
+            if (ipTokenInt == ''):
+                ipTokenInt = 0
+            ipStr = ipStr + str(ipTokenInt)
+            if i != 0:
+                ipStr = ipStr + ':'
+            leftValue %= 65536 ** i
+        print(ipStr)
+        return ipStr
+
+    def getstring(self,randomlength=16):
+        """
+        生成一个指定长度的随机字符串
+        """
+        random_str = ''
+        base_str = 'ABCDEFGHIGKLMNOPQRSTUVWXYZabcdefghigklmnopqrstuvwxyz0123456789'
+        length = len(base_str) - 1
+        for i in range(randomlength):
+            random_str += base_str[random.randint(0, length)]
+        print(random_str)
+        return random_str
+# if __name__ == '__main__':
+#     ipandstring = ipandstring()
+#     print(ipandstring.ipv6())
\ No newline at end of file