prompt: You will be provided with a partial code base and an issue statement explaining a problem to resolve.
  <issue>
  Twitter asks for authorization even though I've already authorized Gittip
  As of #1369 Twitter is now asking me to authorize Giitip even though I've already done so.
  
  ![screen shot 2014-02-26 at 4 45 45 pm](https://f.cloud.github.com/assets/688886/2276800/fac5f68c-9f37-11e3-9dcc-5c77d35c6aa5.png)
  
  <bountysource-plugin>
  
  ---
  
  Want to back this issue? **[Place a bounty on it!](https://www.bountysource.com/issues/1428788-twitter-asks-for-authorization-even-though-i-ve-already-authorized-gittip?utm_campaign=plugin&utm_content=tracker%2F85909&utm_medium=issues&utm_source=github)** We accept bounties via [Bountysource](https://www.bountysource.com/?utm_campaign=plugin&utm_content=tracker%2F85909&utm_medium=issues&utm_source=github).
  </bountysource-plugin>
  
  Twitter asks for authorization even though I've already authorized Gittip
  As of #1369 Twitter is now asking me to authorize Giitip even though I've already done so.
  
  ![screen shot 2014-02-26 at 4 45 45 pm](https://f.cloud.github.com/assets/688886/2276800/fac5f68c-9f37-11e3-9dcc-5c77d35c6aa5.png)
  
  <bountysource-plugin>
  
  ---
  
  Want to back this issue? **[Place a bounty on it!](https://www.bountysource.com/issues/1428788-twitter-asks-for-authorization-even-though-i-ve-already-authorized-gittip?utm_campaign=plugin&utm_content=tracker%2F85909&utm_medium=issues&utm_source=github)** We accept bounties via [Bountysource](https://www.bountysource.com/?utm_campaign=plugin&utm_content=tracker%2F85909&utm_medium=issues&utm_source=github).
  </bountysource-plugin>
  
  
  </issue>
  <code>
  [start of gratipay/elsewhere/twitter.py]
  1 from __future__ import absolute_import, division, print_function, unicode_literals
  2 
  3 from gratipay.elsewhere import PlatformOAuth1
  4 from gratipay.elsewhere._extractors import key, not_available
  5 
  6 
  7 class Twitter(PlatformOAuth1):
  8 
  9     # Platform attributes
  10     name = 'twitter'
  11     display_name = 'Twitter'
  12     account_url = 'https://twitter.com/{user_name}'
  13 
  14     # Auth attributes
  15     auth_url = 'https://api.twitter.com'
  16 
  17     # API attributes
  18     api_format = 'json'
  19     api_url = 'https://api.twitter.com/1.1'
  20     api_user_info_path = '/users/show.json?screen_name={user_name}'
  21     api_user_self_info_path = '/account/verify_credentials.json'
  22     ratelimit_headers_prefix = 'x-rate-limit-'
  23 
  24     # User info extractors
  25     x_user_id = key('id')
  26     x_user_name = key('screen_name')
  27     x_display_name = key('name')
  28     x_email = not_available
  29     x_avatar_url = key('profile_image_url_https',
  30                        clean=lambda v: v.replace('_normal.', '.'))
  31
  [end of gratipay/elsewhere/twitter.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/gratipay/elsewhere/twitter.py b/gratipay/elsewhere/twitter.py
  --- a/gratipay/elsewhere/twitter.py
  +++ b/gratipay/elsewhere/twitter.py
  @@ -13,6 +13,7 @@
   
       # Auth attributes
       auth_url = 'https://api.twitter.com'
  +    authorize_path = '/oauth/authenticate'
   
       # API attributes
       api_format = 'json'
  
verification_info: {"golden_diff": "diff --git a/gratipay/elsewhere/twitter.py b/gratipay/elsewhere/twitter.py\n--- a/gratipay/elsewhere/twitter.py\n+++ b/gratipay/elsewhere/twitter.py\n@@ -13,6 +13,7 @@\n \n     # Auth attributes\n     auth_url = 'https://api.twitter.com'\n+    authorize_path = '/oauth/authenticate'\n \n     # API attributes\n     api_format = 'json'\n", "issue": "Twitter asks for authorization even though I've already authorized Gittip\nAs of #1369 Twitter is now asking me to authorize Giitip even though I've already done so.\n\n![screen shot 2014-02-26 at 4 45 45 pm](https://f.cloud.github.com/assets/688886/2276800/fac5f68c-9f37-11e3-9dcc-5c77d35c6aa5.png)\n\n<bountysource-plugin>\n\n---\n\nWant to back this issue? **[Place a bounty on it!](https://www.bountysource.com/issues/1428788-twitter-asks-for-authorization-even-though-i-ve-already-authorized-gittip?utm_campaign=plugin&utm_content=tracker%2F85909&utm_medium=issues&utm_source=github)** We accept bounties via [Bountysource](https://www.bountysource.com/?utm_campaign=plugin&utm_content=tracker%2F85909&utm_medium=issues&utm_source=github).\n</bountysource-plugin>\n\nTwitter asks for authorization even though I've already authorized Gittip\nAs of #1369 Twitter is now asking me to authorize Giitip even though I've already done so.\n\n![screen shot 2014-02-26 at 4 45 45 pm](https://f.cloud.github.com/assets/688886/2276800/fac5f68c-9f37-11e3-9dcc-5c77d35c6aa5.png)\n\n<bountysource-plugin>\n\n---\n\nWant to back this issue? **[Place a bounty on it!](https://www.bountysource.com/issues/1428788-twitter-asks-for-authorization-even-though-i-ve-already-authorized-gittip?utm_campaign=plugin&utm_content=tracker%2F85909&utm_medium=issues&utm_source=github)** We accept bounties via [Bountysource](https://www.bountysource.com/?utm_campaign=plugin&utm_content=tracker%2F85909&utm_medium=issues&utm_source=github).\n</bountysource-plugin>\n\n", "before_files": [{"content": "from __future__ import absolute_import, division, print_function, unicode_literals\n\nfrom gratipay.elsewhere import PlatformOAuth1\nfrom gratipay.elsewhere._extractors import key, not_available\n\n\nclass Twitter(PlatformOAuth1):\n\n    # Platform attributes\n    name = 'twitter'\n    display_name = 'Twitter'\n    account_url = 'https://twitter.com/{user_name}'\n\n    # Auth attributes\n    auth_url = 'https://api.twitter.com'\n\n    # API attributes\n    api_format = 'json'\n    api_url = 'https://api.twitter.com/1.1'\n    api_user_info_path = '/users/show.json?screen_name={user_name}'\n    api_user_self_info_path = '/account/verify_credentials.json'\n    ratelimit_headers_prefix = 'x-rate-limit-'\n\n    # User info extractors\n    x_user_id = key('id')\n    x_user_name = key('screen_name')\n    x_display_name = key('name')\n    x_email = not_available\n    x_avatar_url = key('profile_image_url_https',\n                       clean=lambda v: v.replace('_normal.', '.'))\n", "path": "gratipay/elsewhere/twitter.py"}]}