title: FileNotFoundError: [Errno 2] No such file or directory: 'keys_keys.txt'
body: <p>As I'm working with files and cryptography library, I'm have problem reading file. Details are as follows,</p>
  
  <p>Getting following exception: </p>
  
  <pre><code>Traceback (most recent call last):
    File "F:/PyCharm Python Works/OpenCity/main_directory/main_file.py", line 8, in &lt;module&gt;
      fe.encrypt_file(z2[0], z2[1])
    File "F:\PyCharm Python Works\OpenCity\cryptograph\file_encryptor.py", line 4, in encrypt_file
      keys = kr.read_keys()
    File "F:\PyCharm Python Works\OpenCity\cryptograph\key_reader.py", line 3, in read_keys
      f1 = open('keys.key', 'rb')
  FileNotFoundError: [Errno 2] No such file or directory: 'keys.key'
  </code></pre>
  
  <p>cryptograph
  file_decryptor.py:</p>
  
  <pre><code>def decrypt_file(x, y):
  
      from cryptograph import key_reader as kr
      from cryptography.fernet import Fernet
      keys = kr.read_keys()
      key = keys[0]
      input_file = x
      output_file = y
  
      with open(input_file, 'rb') as f:
          data = f.read()
  
      f1 = Fernet(key)
      encrypted = f1.decrypt(data)
  
      with open(output_file, 'wb') as f:
          f.write(encrypted)
  </code></pre>
  
  <p>file_encryptor.py:</p>
  
  <pre><code>def encrypt_file(x, y):
      from cryptograph import key_reader as kr
      from cryptography.fernet import Fernet
      keys = kr.read_keys()
      key = keys[0]
      input_file = x
      output_file = y
  
      with open(input_file, 'rb') as f:
          data = f.read()
  
      f2 = Fernet(key)
      encrypted = f2.encrypt(data)
  
      with open(output_file, 'wb') as f:
          f.write(encrypted)
  </code></pre>
  
  <p>key_reader.py:</p>
  
  <pre><code>def read_keys():
      from typing import List
      f1 = open('keys.key', 'rb')
      f2: List[bytes] = []
      data: bytes
      for data in f1:
          f2.append(data)
      print(f2)
      return f2
  </code></pre>
  
  <p>main_file.py:</p>
  
  <pre><code>from cryptograph import file_encryptor as fe
  from cryptograph import file_decryptor as fd
  z1r = open('files.txt', 'r')
  z2 = []
  for data in z1r:
      data = data.rstrip('\n')
      z2.append(data)
  fe.encrypt_file(z2[0], z2[1])
  fd.decrypt_file(z2[1], z2[2])
  </code></pre>
  
  <p>I have just completed the premium category.
  The crytograph is the problem. Everything is OK, except the main_file which is causing problems. </p>