title: Storing values to init but it keeps overwriting the list when a new file read
body: <p>I have two files and load into the class. File one is loaded and then create a string, then file two will load and create a string again and lastly both in one list. However, when I call the function, it just keep overwriting by the new file. Example, When file 2 is read then it only create strings for file 2 and overwrite file 1.</p>
  
  <pre><code>    class something():
      def getting(self, y):# string input "0" and "1"
          self.y = y #I have two files. y is a file. So if I have 2 files, then it will store 2 times into the self.y. Example, file one have "0" and "1" string
          self.fun1()
  
      def fun1(self):
          self.xx = []
          for i in range(2):
              self.xx.append("{} and {}".format(self.y, i)) #After getting the self.y, then it will append it into self.xx.
              # Example, 0 and 0 then 0 and 1; for y in "0" string.
              # Next, 1 and 0 then 1 and 1; for y in "1" string
              self.take()
  
      def take(self):
          return self.xx
  
  
  
  a = ["0", "1"]
  aaa = something()
  for x in a:
  
      aaa.getting(x)
  
  print(aaa.take())
  </code></pre>
  
  <p>Current output:</p>
  
  <pre><code>['1 and 0', '1 and 1']
  </code></pre>
  
  <p>Expected for the a.take:</p>
  
  <pre><code>['0 and 0', '0 and 1', '1 and 0', '1 and 1']
  </code></pre>