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diff --git a/q01_create_class/build.py b/q01_create_class/build.py
index a0188d6..5cbb432 100644
--- a/q01_create_class/build.py
+++ b/q01_create_class/build.py
@@ -1,15 +1,59 @@
+# %load q01_create_class/build.py
 import pandas as pd
 import numpy as np
-import math
+import math as mt
 
-"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.
 
-    """
+    '''
+
+
+class complex_number:
+    def __init__(self, a, b):
+        self.real=a
+        self.imag=b
+    
+    def __str__(self):
+        return '%s + i%s' % (self.real, self.imag) 
+        
+    def __add__(self,rhs):
+        new_a = self.real + rhs.real
+        new_b = self.imag + rhs.imag
+        return complex_number(new_a,new_b)
+    
+    def __sub__(self,rhs):
+        new_a = self.real - rhs.real
+        new_b = self.imag - rhs.imag
+        return complex_number(new_a,new_b)
+    
+    def __mul__(self,rhs):
+        new_a = (self.real * rhs.real) - (self.imag * rhs.imag)
+        new_b = (self.imag * rhs.real) + (self.real * rhs.imag)
+        return complex_number(new_a,new_b)
+
+    def __truediv__(self,rhs):
+        new_a = (self.real * rhs.real) + (self.imag * rhs.imag)
+        new_b = (self.imag * rhs.real) - (self.real * rhs.imag)
+        den  = rhs.real**2 + rhs.imag**2
+        real = new_a/den
+        imag = new_b/den
+        return (real,imag)
+    
+    def abs(self):
+        return mt.sqrt(self.real**2+self.imag**2)
+    
+    def conjugate(self):
+        return complex_number(self.imag,self.real)
+
+    def argument(self):
+        return mt.degrees(mt.atan(self.real/self.imag))
+
+
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