prompt: You will be provided with a partial code base and an issue statement explaining a problem to resolve.
  <issue>
  [Bug] MISSING for Object Conf cls argument
  # 🐛 Bug
  
  OmegaConf cls argument should not be a mandatory value if target is defined. Can we change this to be an optional value with None being the default?
   
  ** Stack trace/error message **
  ```
  omegaconf.errors.MissingMandatoryValue: Missing mandatory value: scheduler.cls
          full_key: scheduler.cls
          reference_type=ObjectConf
          object_type=ObjectConf
  ```
  
  
  ## System information
  - **Hydra Version** :  1.0.0rc2
  - **Python version** : 3.7.7
  
  
  </issue>
  <code>
  [start of hydra/types.py]
  1 # Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved
  2 from dataclasses import dataclass, field
  3 from enum import Enum
  4 from typing import Any, Callable, Dict
  5 
  6 from omegaconf import MISSING
  7 
  8 TaskFunction = Callable[[Any], Any]
  9 
  10 
  11 @dataclass
  12 # This extends Dict[str, Any] to allow for the deprecated "class" field.
  13 # Once support for class field removed this can stop extending Dict.
  14 class ObjectConf(Dict[str, Any]):
  15     # class, class method or function name
  16     target: str = MISSING
  17 
  18     # parameters to pass to cls when calling it
  19     params: Any = field(default_factory=dict)
  20 
  21     # cls is deprecated, use target, cls will be removed in Hydra 1.1
  22     cls: str = MISSING
  23 
  24     # class is deprecated, use target, class will be removed in Hydra 1.1
  25     # (class is Python keyword and is only supported through DictConfig)
  26     # class: str = MISSING
  27 
  28 
  29 class RunMode(Enum):
  30     RUN = 1
  31     MULTIRUN = 2
  32
  [end of hydra/types.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/hydra/types.py b/hydra/types.py
  --- a/hydra/types.py
  +++ b/hydra/types.py
  @@ -18,13 +18,6 @@
       # parameters to pass to cls when calling it
       params: Any = field(default_factory=dict)
   
  -    # cls is deprecated, use target, cls will be removed in Hydra 1.1
  -    cls: str = MISSING
  -
  -    # class is deprecated, use target, class will be removed in Hydra 1.1
  -    # (class is Python keyword and is only supported through DictConfig)
  -    # class: str = MISSING
  -
   
   class RunMode(Enum):
       RUN = 1
  
verification_info: {"golden_diff": "diff --git a/hydra/types.py b/hydra/types.py\n--- a/hydra/types.py\n+++ b/hydra/types.py\n@@ -18,13 +18,6 @@\n     # parameters to pass to cls when calling it\n     params: Any = field(default_factory=dict)\n \n-    # cls is deprecated, use target, cls will be removed in Hydra 1.1\n-    cls: str = MISSING\n-\n-    # class is deprecated, use target, class will be removed in Hydra 1.1\n-    # (class is Python keyword and is only supported through DictConfig)\n-    # class: str = MISSING\n-\n \n class RunMode(Enum):\n     RUN = 1\n", "issue": "[Bug] MISSING for Object Conf cls argument\n# \ud83d\udc1b Bug\r\n\r\nOmegaConf cls argument should not be a mandatory value if target is defined. Can we change this to be an optional value with None being the default?\r\n \r\n** Stack trace/error message **\r\n```\r\nomegaconf.errors.MissingMandatoryValue: Missing mandatory value: scheduler.cls\r\n        full_key: scheduler.cls\r\n        reference_type=ObjectConf\r\n        object_type=ObjectConf\r\n```\r\n\r\n\r\n## System information\r\n- **Hydra Version** :  1.0.0rc2\r\n- **Python version** : 3.7.7\r\n\n", "before_files": [{"content": "# Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved\nfrom dataclasses import dataclass, field\nfrom enum import Enum\nfrom typing import Any, Callable, Dict\n\nfrom omegaconf import MISSING\n\nTaskFunction = Callable[[Any], Any]\n\n\n@dataclass\n# This extends Dict[str, Any] to allow for the deprecated \"class\" field.\n# Once support for class field removed this can stop extending Dict.\nclass ObjectConf(Dict[str, Any]):\n    # class, class method or function name\n    target: str = MISSING\n\n    # parameters to pass to cls when calling it\n    params: Any = field(default_factory=dict)\n\n    # cls is deprecated, use target, cls will be removed in Hydra 1.1\n    cls: str = MISSING\n\n    # class is deprecated, use target, class will be removed in Hydra 1.1\n    # (class is Python keyword and is only supported through DictConfig)\n    # class: str = MISSING\n\n\nclass RunMode(Enum):\n    RUN = 1\n    MULTIRUN = 2\n", "path": "hydra/types.py"}]}