diff --git a/__pycache__/__init__.cpython-36.pyc b/__pycache__/__init__.cpython-36.pyc
index a600305..f6c9a04 100644
Binary files a/__pycache__/__init__.cpython-36.pyc and b/__pycache__/__init__.cpython-36.pyc differ
diff --git a/q01_create_class/__pycache__/__init__.cpython-36.pyc b/q01_create_class/__pycache__/__init__.cpython-36.pyc
index 09a1efa..742e28d 100644
Binary files a/q01_create_class/__pycache__/__init__.cpython-36.pyc and b/q01_create_class/__pycache__/__init__.cpython-36.pyc differ
diff --git a/q01_create_class/__pycache__/build.cpython-36.pyc b/q01_create_class/__pycache__/build.cpython-36.pyc
index 9f53117..684f337 100644
Binary files a/q01_create_class/__pycache__/build.cpython-36.pyc and b/q01_create_class/__pycache__/build.cpython-36.pyc differ
diff --git a/q01_create_class/build.py b/q01_create_class/build.py
index a0188d6..a08bc3a 100644
--- a/q01_create_class/build.py
+++ b/q01_create_class/build.py
@@ -1,15 +1,55 @@
+# %load q01_create_class/build.py
 import pandas as pd
 import numpy as np
 import math
 
-"write your solution here"
+'write your solution here'
 
 
 class complex_number:
-    """The complex number class.
+    '''The complex number class.
 
     Attributes:
     attr1 (x): Real part of complex number.
-    attr2 (y): Imaginary part of complex number.
+    attr2 (y): Imaginary part of complex number.'''
+    def __init__(self,real,imag):
+        self.real= real
+        self.imag=imag
+    def __add__(self,another_complex):
+        a=self.real + another_complex.real
+        b=self.imag + another_complex.imag
+        c=complex_number(a,b)
+        return c
+#     def __repr__(self):
+#         return str(self.real)+ ' + ' + str(self.imag)+'i'
+#         return (self.real,self.imag)
+    def __sub__(self,another_complex):
+        a=self.real - another_complex.real
+        b=self.imag - another_complex.imag
+        c=complex_number(a,b)
+        return c
+    def __mul__(self,another_complex):
+        a=self.real * another_complex.real - self.imag*another_complex.imag
+        b=self.real * another_complex.imag + self.imag*another_complex.real
+        c=complex_number(a,b)
+        return c
+    def __truediv__(self,another_complex):
+        a=((self.real*another_complex.real)+(self.imag*another_complex.imag))/(another_complex.real**2 + another_complex.imag**2)
+        b=((self.imag*another_complex.real)-(self.real*another_complex.imag))/(another_complex.real**2 + another_complex.imag**2)
+        c=complex_number(a,b)
+        return a,b
+    def abs(self):
+        return (self.real**2 + self.imag**2)**0.5
+    def argument(self):
+        return math.degrees(math.atan(self.imag/self.real))
+
+a=complex_number(2,3)
+
+b=complex_number(4,5)
+b
+a/b
+c=a+b
+c.imag
+a.argument()
+
 
-    """
diff --git a/q01_create_class/tests/__pycache__/__init__.cpython-36.pyc b/q01_create_class/tests/__pycache__/__init__.cpython-36.pyc
index 58575f1..ce2d32d 100644
Binary files a/q01_create_class/tests/__pycache__/__init__.cpython-36.pyc and b/q01_create_class/tests/__pycache__/__init__.cpython-36.pyc differ
diff --git a/q01_create_class/tests/__pycache__/test_complex_number.cpython-36.pyc b/q01_create_class/tests/__pycache__/test_complex_number.cpython-36.pyc
index b378e09..c3acfc9 100644
Binary files a/q01_create_class/tests/__pycache__/test_complex_number.cpython-36.pyc and b/q01_create_class/tests/__pycache__/test_complex_number.cpython-36.pyc differ