prompt: You will be provided with a partial code base and an issue statement explaining a problem to resolve.
  <issue>
  Unable to launch the debugger
  Getting the following error in master when debugging in VSC:
  ```
  Could not connect to None: 60857
  Traceback (most recent call last):
    File "/Users/donjayamanne/Desktop/Development/vscode/ptvsd/ptvsd/pydevd/pydevd.py", line 1620, in main
      debugger.connect(host, port)
    File "/Users/donjayamanne/Desktop/Development/vscode/ptvsd/ptvsd/pydevd/pydevd.py", line 326, in connect
      s = start_server(port)
    File "/Users/donjayamanne/Desktop/Development/vscode/ptvsd/ptvsd/wrapper.py", line 1766, in start_server
      server = _create_server(port)
    File "/Users/donjayamanne/Desktop/Development/vscode/ptvsd/ptvsd/wrapper.py", line 1701, in _create_server
      server.bind(('127.0.0.1', port))
  OSError: [Errno 48] Address already in u
  ```
  
  </issue>
  <code>
  [start of ptvsd/debugger.py]
  1 # Copyright (c) Microsoft Corporation. All rights reserved.
  2 # Licensed under the MIT License. See LICENSE in the project root
  3 # for license information.
  4 
  5 from ptvsd.__main__ import run_module, run_file
  6 
  7 
  8 __author__ = "Microsoft Corporation <ptvshelp@microsoft.com>"
  9 __version__ = "4.0.0a5"
  10 
  11 # TODO: not needed?
  12 DONT_DEBUG = []
  13 
  14 
  15 def debug(filename, port_num, debug_id, debug_options, run_as, **kwargs):
  16     # TODO: docstring
  17     address = (None, port_num)
  18     if run_as == 'module':
  19         run_module(address, filename, **kwargs)
  20     else:
  21         run_file(address, filename, **kwargs)
  22
  [end of ptvsd/debugger.py]
  </code>
  
  I need you to solve this issue by generating a single patch file that I can apply directly to this repository using git apply. Please respond with a single patch file in the following format.
  <patch>
  diff --git a/file.py b/file.py
  --- a/file.py
  +++ b/file.py
  @@ -1,27 +1,35 @@
   def euclidean(a, b):
  -    while b:
  -        a, b = b, a % b
  -    return a
  +    if b == 0:
  +        return a
  +    return euclidean(b, a % b)
   
   
   def bresenham(x0, y0, x1, y1):
       points = []
       dx = abs(x1 - x0)
       dy = abs(y1 - y0)
  -    sx = 1 if x0 < x1 else -1
  -    sy = 1 if y0 < y1 else -1
  -    err = dx - dy
  +    x, y = x0, y0
  +    sx = -1 if x0 > x1 else 1
  +    sy = -1 if y0 > y1 else 1
   
  -    while True:
  -        points.append((x0, y0))
  -        if x0 == x1 and y0 == y1:
  -            break
  -        e2 = 2 * err
  -        if e2 > -dy:
  -            err -= dy
  -            x0 += sx
  -        if e2 < dx:
  -            err += dx
  -            y0 += sy
  +    if dx > dy:
  +        err = dx / 2.0
  +        while x != x1:
  +            points.append((x, y))
  +            err -= dy
  +            if err < 0:
  +                y += sy
  +                err += dx
  +            x += sx
  +    else:
  +        err = dy / 2.0
  +        while y != y1:
  +            points.append((x, y))
  +            err -= dx
  +            if err < 0:
  +                x += sx
  +                err += dy
  +            y += sy
  +
  +    points.append((x, y))
       return points
  
  </patch>
golden_diff: diff --git a/ptvsd/debugger.py b/ptvsd/debugger.py
  --- a/ptvsd/debugger.py
  +++ b/ptvsd/debugger.py
  @@ -14,7 +14,7 @@
   
   def debug(filename, port_num, debug_id, debug_options, run_as, **kwargs):
       # TODO: docstring
  -    address = (None, port_num)
  +    address = ('localhost', port_num)
       if run_as == 'module':
           run_module(address, filename, **kwargs)
       else:
  
verification_info: {"golden_diff": "diff --git a/ptvsd/debugger.py b/ptvsd/debugger.py\n--- a/ptvsd/debugger.py\n+++ b/ptvsd/debugger.py\n@@ -14,7 +14,7 @@\n \n def debug(filename, port_num, debug_id, debug_options, run_as, **kwargs):\n     # TODO: docstring\n-    address = (None, port_num)\n+    address = ('localhost', port_num)\n     if run_as == 'module':\n         run_module(address, filename, **kwargs)\n     else:\n", "issue": "Unable to launch the debugger\nGetting the following error in master when debugging in VSC:\r\n```\r\nCould not connect to None: 60857\r\nTraceback (most recent call last):\r\n  File \"/Users/donjayamanne/Desktop/Development/vscode/ptvsd/ptvsd/pydevd/pydevd.py\", line 1620, in main\r\n    debugger.connect(host, port)\r\n  File \"/Users/donjayamanne/Desktop/Development/vscode/ptvsd/ptvsd/pydevd/pydevd.py\", line 326, in connect\r\n    s = start_server(port)\r\n  File \"/Users/donjayamanne/Desktop/Development/vscode/ptvsd/ptvsd/wrapper.py\", line 1766, in start_server\r\n    server = _create_server(port)\r\n  File \"/Users/donjayamanne/Desktop/Development/vscode/ptvsd/ptvsd/wrapper.py\", line 1701, in _create_server\r\n    server.bind(('127.0.0.1', port))\r\nOSError: [Errno 48] Address already in u\r\n```\n", "before_files": [{"content": "# Copyright (c) Microsoft Corporation. All rights reserved.\n# Licensed under the MIT License. See LICENSE in the project root\n# for license information.\n\nfrom ptvsd.__main__ import run_module, run_file\n\n\n__author__ = \"Microsoft Corporation <ptvshelp@microsoft.com>\"\n__version__ = \"4.0.0a5\"\n\n# TODO: not needed?\nDONT_DEBUG = []\n\n\ndef debug(filename, port_num, debug_id, debug_options, run_as, **kwargs):\n    # TODO: docstring\n    address = (None, port_num)\n    if run_as == 'module':\n        run_module(address, filename, **kwargs)\n    else:\n        run_file(address, filename, **kwargs)\n", "path": "ptvsd/debugger.py"}]}