title: Importing main class file to the child class file in Python
body: <p>So, basically, I have a folder called "Material" with two files in it: "Material.py" and "ElasticMaterial.py". Also, I have classes in each of the files called Material and ElasticMaterial respectively. Also, ElasticMaterial is a subclass of Material, hence, its class definition is:</p>
  
  <pre><code>class ElasticMaterial(Material):
      def __init__(self,StressState):
  
          self.StressState = StressState
          if self.StressState=='threed':
              self.lv=6  #lv is length of stress and strain vectors
          else:
              self.lv=4
  </code></pre>
  
  <p>If I am importing Material class as any of the following options:</p>
  
  <pre><code>import Material.Material
  
  from Material.Material import Material
  
  from . import Material
  </code></pre>
  
  <p>I am getting the error: "module.<strong>init</strong>() takes at most 2 arguments (3 given)"</p>
  
  <p>Also, can anyone suggest any good course on Python OOP and Packages? I am using Python 3.6.</p>
  
  <p>P.S. I am trying to package my software such that each class is contained in its individual file.
  Adding Code from Material.py file</p>
  
  <pre><code>import numpy as np
  from Material.ElasticMaterial import ElasticMaterial
  class Material(object):
  
      def newMaterial(matPhysLaw, stressState):
          if (matPhysLaw=="elastic"):
  
              return ElasticMaterial(stressState)
  </code></pre>