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diff --git a/q01_create_class/build.py b/q01_create_class/build.py
index a0188d6..5030068 100644
--- a/q01_create_class/build.py
+++ b/q01_create_class/build.py
@@ -1,15 +1,53 @@
+# %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.
 
-    """
+    '''
+    def __init__(self, real, imag):
+        self.real = real
+        self.imag = imag
+    
+    def __add__(self, other):
+        return complex_number(self.real+other.real, self.imag+other.imag)
+
+    def __sub__(self, other):
+        return complex_number(self.real-other.real, self.imag-other.imag)
+    
+    def __mul__(self, other):
+        return complex_number(self.real*other.real-self.imag*other.imag, self.real*other.imag+self.imag*other.real)
+    
+    def __truediv__(self, other):
+        num1 = (self.real*other.real + other.imag*self.imag)
+        deno = (other.real**2 + other.imag**2)
+        num2= ((self.imag*other.real)-(self.real*other.imag))
+        return ((num1/deno),(num2/deno))
+        
+    def abs(self):
+        return math.sqrt(self.real**2 + self.imag**2)
+
+    def argument(self):
+        a=math.atan2(self.imag,self.real)
+        return math.degrees(a)        
+    
+    def conjugate(self):
+        a=self.real
+        b=self.imag*(-1)
+        return complex_number(a,b)
+        
+    def __str__(self, precision=2):
+        return str(('%.'+'%df'%precision)%float(self.real))+('+' if self.imag>=0 else '-')+str(('%.'+'%df'%precision)%float(abs(self.imag)))+'i'
+
+
+
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