diff --git a/bin/__init__.py b/bin/__init__.py
index 3b39b3d..153b135 100644
--- a/bin/__init__.py
+++ b/bin/__init__.py
@@ -6,9 +6,9 @@ mail: 3695888@qq.com
 #
 
 # import in this folder
-import main
-import tools
-import client
-import server
-import configs
-import delivery
+import bin.main
+import bin.tools
+import bin.client
+import bin.server
+import bin.configs
+import bin.delivery
diff --git a/bin/main.py b/bin/main.py
index 2e68e69..11a2111 100644
--- a/bin/main.py
+++ b/bin/main.py
@@ -11,8 +11,8 @@ import time
 import logging
 
 # 直接导入
-import server
-import client
+import bin.server as server
+import bin.client as client
 
 
 class Game():
diff --git a/bin/tools.py b/bin/tools.py
index a19cb76..9452a57 100644
--- a/bin/tools.py
+++ b/bin/tools.py
@@ -25,6 +25,14 @@ Physics calculation
 """
 
 
+def F_D(A, B):
+    pass
+
+
+def F_Mu():
+    pass
+
+
 def D_C(listA, listB):  # stand for Duplicate check
     """
     usage:\n
diff --git a/test.py b/test.py
index d06ef0e..9c785f9 100644
--- a/test.py
+++ b/test.py
@@ -4,6 +4,7 @@ mail: 3695888@qq.com
 """
 
 import bin
+import decimal
 
 A = [2.573, 3, ["m", "kg"], ["N", "s"]]
 B = [2.45, -7, ["N", "kg"], ["m", "s"]]
@@ -15,6 +16,7 @@ print("B = ", B)
 print("C = ", C)
 print("D = ", D)
 
+
 a = bin.tools.S_N_M(A, B)
 b = bin.tools.S_N_D(A, B)
 c = bin.tools.S_N_M(b, B)
@@ -30,3 +32,8 @@ f = bin.tools.S_N_M(A, bin.tools.S_N_M(B, bin.tools.S_N_M(C, D)))
 
 print("A * B * C * D = ", e)
 print("A * B * C * D = ", f)
+
+e = decimal.Decimal('0.1')
+f = 0.1
+
+print(type(e), type(f))