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diff --git a/q01_create_class/__pycache__/build.cpython-36.pyc b/q01_create_class/__pycache__/build.cpython-36.pyc
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diff --git a/q01_create_class/build.py b/q01_create_class/build.py
index a0188d6..866e540 100644
--- a/q01_create_class/build.py
+++ b/q01_create_class/build.py
@@ -1,15 +1,71 @@
+# %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.
+class complex_number(object):
+    '''The complex number class.
 
     Attributes:
     attr1 (x): Real part of complex number.
     attr2 (y): Imaginary part of complex number.
 
-    """
+    '''
+    
+    def __init__(self,real=0.0,imag=0.0):
+        self.real = real
+        self.imag = imag
+        
+    def __str__(self):
+        if self.imag < 0.0:
+            return '{}-{}i'.format(self.real,abs(self.imag))
+        else:
+            return '{}+{}i'.format(self.real,self.imag)
+    
+        
+    def __add__(self,other):
+        c = self.real + other.real
+        d = self.imag + other.imag
+        return complex_number(c,d)
+    
+    def __sub__(self, others):
+        return complex_number(self.real - others.real, self.imag - others.imag)
+    
+    def __mul__(self, others):
+        return complex_number(self.real*others.real-self.imag*others.imag, self.real*others.imag+self.imag*others.real)
+    
+    def __truediv__(self,others):
+        a = (self.real*others.real+self.imag*others.imag)/(others.real**2 + others.imag**2) 
+        b = (self.imag*others.real-self.real*others.imag)/(others.real**2 + others.imag**2)
+        return a,b                    
+    
+        
+    def abs(self):
+        return np.sqrt(np.square(self.real)+np.square(self.imag))
+           
+    def argument(self):
+        return math.degrees(math.atan(self.real/self.imag))
+        
+        
+    def conjugate(self):
+        return complex_number(self.real, -self.imag)
+
+d1 = complex_number(5,5)
+print(d1)
+
+d1 = complex_number(5,1)
+d2 = complex_number(6,0)
+print(d1 + d2)
+# print(d2 - d1)
+print(d2 / d1)
+# print(d2 * d1)
+# print(d1.conjugate())
+# print(d2.conjugate())
+# print(d1.abs())
+# print(d2.abs())
+# print(d1.argument())
+
+
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