prompt: You will be provided with a partial code base and an issue statement explaining a problem to resolve.
  <issue>
  error launching Flocker
  I've Anaconda with python 3.6 & Mesa 0.8.1
  
  I launch Flocker's run.py and I get this error:
  ```
  Flockers e$ python run.py
  Traceback (most recent call last):
    File "run.py", line 1, in <module>
      from flockers.server import server
    File "/Users/e/Dropbox/devlib/notebooks/mesa-master/examples/Flockers/flockers/server.py", line 20, in <module>
      server = ModularServer(BoidModel, [boid_canvas], "Boids", model_params)
    File "/Users/e/anaconda3/lib/python3.6/site-packages/mesa/visualization/ModularVisualization.py", line 287, in __init__
      self.reset_model()
    File "/Users/e/anaconda3/lib/python3.6/site-packages/mesa/visualization/ModularVisualization.py", line 313, in reset_model
      self.model = self.model_cls(**model_params)
  TypeError: __init__() got an unexpected keyword argument 'N'
  ```
  
  </issue>
  <code>
  [start of examples/Flockers/flockers/server.py]
  1 from mesa.visualization.ModularVisualization import ModularServer
  2 
  3 from .model import BoidModel
  4 from .SimpleContinuousModule import SimpleCanvas
  5 
  6 
  7 def boid_draw(agent):
  8     return {"Shape": "circle", "r": 2, "Filled": "true", "Color": "Red"}
  9 
  10 boid_canvas = SimpleCanvas(boid_draw, 500, 500)
  11 model_params = {
  12     "N": 100,
  13     "width": 100,
  14     "height": 100,
  15     "speed": 5,
  16     "vision": 10,
  17     "separation": 2
  18 }
  19 
  20 server = ModularServer(BoidModel, [boid_canvas], "Boids", model_params)
  21
  [end of examples/Flockers/flockers/server.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/examples/Flockers/flockers/server.py b/examples/Flockers/flockers/server.py
  --- a/examples/Flockers/flockers/server.py
  +++ b/examples/Flockers/flockers/server.py
  @@ -9,7 +9,7 @@
   
   boid_canvas = SimpleCanvas(boid_draw, 500, 500)
   model_params = {
  -    "N": 100,
  +    "population": 100,
       "width": 100,
       "height": 100,
       "speed": 5,
  
verification_info: {"golden_diff": "diff --git a/examples/Flockers/flockers/server.py b/examples/Flockers/flockers/server.py\n--- a/examples/Flockers/flockers/server.py\n+++ b/examples/Flockers/flockers/server.py\n@@ -9,7 +9,7 @@\n \n boid_canvas = SimpleCanvas(boid_draw, 500, 500)\n model_params = {\n-    \"N\": 100,\n+    \"population\": 100,\n     \"width\": 100,\n     \"height\": 100,\n     \"speed\": 5,\n", "issue": "error launching Flocker\nI've Anaconda with python 3.6 & Mesa 0.8.1\r\n\r\nI launch Flocker's run.py and I get this error:\r\n```\r\nFlockers e$ python run.py\r\nTraceback (most recent call last):\r\n  File \"run.py\", line 1, in <module>\r\n    from flockers.server import server\r\n  File \"/Users/e/Dropbox/devlib/notebooks/mesa-master/examples/Flockers/flockers/server.py\", line 20, in <module>\r\n    server = ModularServer(BoidModel, [boid_canvas], \"Boids\", model_params)\r\n  File \"/Users/e/anaconda3/lib/python3.6/site-packages/mesa/visualization/ModularVisualization.py\", line 287, in __init__\r\n    self.reset_model()\r\n  File \"/Users/e/anaconda3/lib/python3.6/site-packages/mesa/visualization/ModularVisualization.py\", line 313, in reset_model\r\n    self.model = self.model_cls(**model_params)\r\nTypeError: __init__() got an unexpected keyword argument 'N'\r\n```\n", "before_files": [{"content": "from mesa.visualization.ModularVisualization import ModularServer\n\nfrom .model import BoidModel\nfrom .SimpleContinuousModule import SimpleCanvas\n\n\ndef boid_draw(agent):\n    return {\"Shape\": \"circle\", \"r\": 2, \"Filled\": \"true\", \"Color\": \"Red\"}\n\nboid_canvas = SimpleCanvas(boid_draw, 500, 500)\nmodel_params = {\n    \"N\": 100,\n    \"width\": 100,\n    \"height\": 100,\n    \"speed\": 5,\n    \"vision\": 10,\n    \"separation\": 2\n}\n\nserver = ModularServer(BoidModel, [boid_canvas], \"Boids\", model_params)\n", "path": "examples/Flockers/flockers/server.py"}]}