We are currently solving the following issue within our repository. Here is the issue text:
--- BEGIN ISSUE ---
Deprecate Reppy support
https://github.com/scrapy/scrapy/issues/5226#issuecomment-897621867

--- END ISSUE ---

Below are some code segments, each from a relevant file. One or more of these files may contain bugs.
--- BEGIN FILES ---
Path: `scrapy/robotstxt.py`
Content:
```
1 import logging
2 import sys
3 from abc import ABCMeta, abstractmethod
4 
5 from scrapy.utils.python import to_unicode
6 
7 logger = logging.getLogger(__name__)
8 
9 
10 def decode_robotstxt(robotstxt_body, spider, to_native_str_type=False):
11     try:
12         if to_native_str_type:
13             robotstxt_body = to_unicode(robotstxt_body)
14         else:
15             robotstxt_body = robotstxt_body.decode("utf-8")
16     except UnicodeDecodeError:
17         # If we found garbage or robots.txt in an encoding other than UTF-8, disregard it.
18         # Switch to 'allow all' state.
19         logger.warning(
20             "Failure while parsing robots.txt. File either contains garbage or "
21             "is in an encoding other than UTF-8, treating it as an empty file.",
22             exc_info=sys.exc_info(),
23             extra={"spider": spider},
24         )
25         robotstxt_body = ""
26     return robotstxt_body
27 
28 
29 class RobotParser(metaclass=ABCMeta):
30     @classmethod
31     @abstractmethod
32     def from_crawler(cls, crawler, robotstxt_body):
33         """Parse the content of a robots.txt_ file as bytes. This must be a class method.
34         It must return a new instance of the parser backend.
35 
36         :param crawler: crawler which made the request
37         :type crawler: :class:`~scrapy.crawler.Crawler` instance
38 
39         :param robotstxt_body: content of a robots.txt_ file.
40         :type robotstxt_body: bytes
41         """
42         pass
43 
44     @abstractmethod
45     def allowed(self, url, user_agent):
46         """Return ``True`` if  ``user_agent`` is allowed to crawl ``url``, otherwise return ``False``.
47 
48         :param url: Absolute URL
49         :type url: str
50 
51         :param user_agent: User agent
52         :type user_agent: str
53         """
54         pass
55 
56 
57 class PythonRobotParser(RobotParser):
58     def __init__(self, robotstxt_body, spider):
59         from urllib.robotparser import RobotFileParser
60 
61         self.spider = spider
62         robotstxt_body = decode_robotstxt(
63             robotstxt_body, spider, to_native_str_type=True
64         )
65         self.rp = RobotFileParser()
66         self.rp.parse(robotstxt_body.splitlines())
67 
68     @classmethod
69     def from_crawler(cls, crawler, robotstxt_body):
70         spider = None if not crawler else crawler.spider
71         o = cls(robotstxt_body, spider)
72         return o
73 
74     def allowed(self, url, user_agent):
75         user_agent = to_unicode(user_agent)
76         url = to_unicode(url)
77         return self.rp.can_fetch(user_agent, url)
78 
79 
80 class ReppyRobotParser(RobotParser):
81     def __init__(self, robotstxt_body, spider):
82         from reppy.robots import Robots
83 
84         self.spider = spider
85         self.rp = Robots.parse("", robotstxt_body)
86 
87     @classmethod
88     def from_crawler(cls, crawler, robotstxt_body):
89         spider = None if not crawler else crawler.spider
90         o = cls(robotstxt_body, spider)
91         return o
92 
93     def allowed(self, url, user_agent):
94         return self.rp.allowed(url, user_agent)
95 
96 
97 class RerpRobotParser(RobotParser):
98     def __init__(self, robotstxt_body, spider):
99         from robotexclusionrulesparser import RobotExclusionRulesParser
100 
101         self.spider = spider
102         self.rp = RobotExclusionRulesParser()
103         robotstxt_body = decode_robotstxt(robotstxt_body, spider)
104         self.rp.parse(robotstxt_body)
105 
106     @classmethod
107     def from_crawler(cls, crawler, robotstxt_body):
108         spider = None if not crawler else crawler.spider
109         o = cls(robotstxt_body, spider)
110         return o
111 
112     def allowed(self, url, user_agent):
113         user_agent = to_unicode(user_agent)
114         url = to_unicode(url)
115         return self.rp.is_allowed(user_agent, url)
116 
117 
118 class ProtegoRobotParser(RobotParser):
119     def __init__(self, robotstxt_body, spider):
120         from protego import Protego
121 
122         self.spider = spider
123         robotstxt_body = decode_robotstxt(robotstxt_body, spider)
124         self.rp = Protego.parse(robotstxt_body)
125 
126     @classmethod
127     def from_crawler(cls, crawler, robotstxt_body):
128         spider = None if not crawler else crawler.spider
129         o = cls(robotstxt_body, spider)
130         return o
131 
132     def allowed(self, url, user_agent):
133         user_agent = to_unicode(user_agent)
134         url = to_unicode(url)
135         return self.rp.can_fetch(url, user_agent)
136
```
--- END FILES ---

Please first localize the bug based on the issue statement, and then generate a patch according to the `git diff` format fenced by three backticks.

Here is an example:

```diff
diff --git a/examples/server_async.py b/examples/server_async.py
--- a/examples/server_async.py
+++ b/examples/server_async.py
@@ -313,4 +313,4 @@
 
 
 if __name__ == "__main__":
-    asyncio.run(run_async_server("."), debug=True)
+    asyncio.run(run_async_server(), debug=True)
diff --git a/examples/server_sync.py b/examples/server_sync.py
--- a/examples/server_sync.py
+++ b/examples/server_sync.py
@@ -313,5 +313,5 @@
 
 
 if __name__ == "__main__":
-    server = run_sync_server(".")
+    server = run_sync_server()
     server.shutdown()

```

diff --git a/scrapy/robotstxt.py b/scrapy/robotstxt.py
--- a/scrapy/robotstxt.py
+++ b/scrapy/robotstxt.py
@@ -1,7 +1,9 @@
 import logging
 import sys
 from abc import ABCMeta, abstractmethod
+from warnings import warn
 
+from scrapy.exceptions import ScrapyDeprecationWarning
 from scrapy.utils.python import to_unicode
 
 logger = logging.getLogger(__name__)
@@ -79,6 +81,7 @@
 
 class ReppyRobotParser(RobotParser):
     def __init__(self, robotstxt_body, spider):
+        warn("ReppyRobotParser is deprecated.", ScrapyDeprecationWarning, stacklevel=2)
         from reppy.robots import Robots
 
         self.spider = spider

{"golden_diff": "diff --git a/scrapy/robotstxt.py b/scrapy/robotstxt.py\n--- a/scrapy/robotstxt.py\n+++ b/scrapy/robotstxt.py\n@@ -1,7 +1,9 @@\n import logging\n import sys\n from abc import ABCMeta, abstractmethod\n+from warnings import warn\n \n+from scrapy.exceptions import ScrapyDeprecationWarning\n from scrapy.utils.python import to_unicode\n \n logger = logging.getLogger(__name__)\n@@ -79,6 +81,7 @@\n \n class ReppyRobotParser(RobotParser):\n     def __init__(self, robotstxt_body, spider):\n+        warn(\"ReppyRobotParser is deprecated.\", ScrapyDeprecationWarning, stacklevel=2)\n         from reppy.robots import Robots\n \n         self.spider = spider\n", "issue": "Deprecate Reppy support\nhttps://github.com/scrapy/scrapy/issues/5226#issuecomment-897621867\n", "before_files": [{"content": "import logging\nimport sys\nfrom abc import ABCMeta, abstractmethod\n\nfrom scrapy.utils.python import to_unicode\n\nlogger = logging.getLogger(__name__)\n\n\ndef decode_robotstxt(robotstxt_body, spider, to_native_str_type=False):\n    try:\n        if to_native_str_type:\n            robotstxt_body = to_unicode(robotstxt_body)\n        else:\n            robotstxt_body = robotstxt_body.decode(\"utf-8\")\n    except UnicodeDecodeError:\n        # If we found garbage or robots.txt in an encoding other than UTF-8, disregard it.\n        # Switch to 'allow all' state.\n        logger.warning(\n            \"Failure while parsing robots.txt. File either contains garbage or \"\n            \"is in an encoding other than UTF-8, treating it as an empty file.\",\n            exc_info=sys.exc_info(),\n            extra={\"spider\": spider},\n        )\n        robotstxt_body = \"\"\n    return robotstxt_body\n\n\nclass RobotParser(metaclass=ABCMeta):\n    @classmethod\n    @abstractmethod\n    def from_crawler(cls, crawler, robotstxt_body):\n        \"\"\"Parse the content of a robots.txt_ file as bytes. This must be a class method.\n        It must return a new instance of the parser backend.\n\n        :param crawler: crawler which made the request\n        :type crawler: :class:`~scrapy.crawler.Crawler` instance\n\n        :param robotstxt_body: content of a robots.txt_ file.\n        :type robotstxt_body: bytes\n        \"\"\"\n        pass\n\n    @abstractmethod\n    def allowed(self, url, user_agent):\n        \"\"\"Return ``True`` if  ``user_agent`` is allowed to crawl ``url``, otherwise return ``False``.\n\n        :param url: Absolute URL\n        :type url: str\n\n        :param user_agent: User agent\n        :type user_agent: str\n        \"\"\"\n        pass\n\n\nclass PythonRobotParser(RobotParser):\n    def __init__(self, robotstxt_body, spider):\n        from urllib.robotparser import RobotFileParser\n\n        self.spider = spider\n        robotstxt_body = decode_robotstxt(\n            robotstxt_body, spider, to_native_str_type=True\n        )\n        self.rp = RobotFileParser()\n        self.rp.parse(robotstxt_body.splitlines())\n\n    @classmethod\n    def from_crawler(cls, crawler, robotstxt_body):\n        spider = None if not crawler else crawler.spider\n        o = cls(robotstxt_body, spider)\n        return o\n\n    def allowed(self, url, user_agent):\n        user_agent = to_unicode(user_agent)\n        url = to_unicode(url)\n        return self.rp.can_fetch(user_agent, url)\n\n\nclass ReppyRobotParser(RobotParser):\n    def __init__(self, robotstxt_body, spider):\n        from reppy.robots import Robots\n\n        self.spider = spider\n        self.rp = Robots.parse(\"\", robotstxt_body)\n\n    @classmethod\n    def from_crawler(cls, crawler, robotstxt_body):\n        spider = None if not crawler else crawler.spider\n        o = cls(robotstxt_body, spider)\n        return o\n\n    def allowed(self, url, user_agent):\n        return self.rp.allowed(url, user_agent)\n\n\nclass RerpRobotParser(RobotParser):\n    def __init__(self, robotstxt_body, spider):\n        from robotexclusionrulesparser import RobotExclusionRulesParser\n\n        self.spider = spider\n        self.rp = RobotExclusionRulesParser()\n        robotstxt_body = decode_robotstxt(robotstxt_body, spider)\n        self.rp.parse(robotstxt_body)\n\n    @classmethod\n    def from_crawler(cls, crawler, robotstxt_body):\n        spider = None if not crawler else crawler.spider\n        o = cls(robotstxt_body, spider)\n        return o\n\n    def allowed(self, url, user_agent):\n        user_agent = to_unicode(user_agent)\n        url = to_unicode(url)\n        return self.rp.is_allowed(user_agent, url)\n\n\nclass ProtegoRobotParser(RobotParser):\n    def __init__(self, robotstxt_body, spider):\n        from protego import Protego\n\n        self.spider = spider\n        robotstxt_body = decode_robotstxt(robotstxt_body, spider)\n        self.rp = Protego.parse(robotstxt_body)\n\n    @classmethod\n    def from_crawler(cls, crawler, robotstxt_body):\n        spider = None if not crawler else crawler.spider\n        o = cls(robotstxt_body, spider)\n        return o\n\n    def allowed(self, url, user_agent):\n        user_agent = to_unicode(user_agent)\n        url = to_unicode(url)\n        return self.rp.can_fetch(url, user_agent)\n", "path": "scrapy/robotstxt.py"}], "after_files": [{"content": "import logging\nimport sys\nfrom abc import ABCMeta, abstractmethod\nfrom warnings import warn\n\nfrom scrapy.exceptions import ScrapyDeprecationWarning\nfrom scrapy.utils.python import to_unicode\n\nlogger = logging.getLogger(__name__)\n\n\ndef decode_robotstxt(robotstxt_body, spider, to_native_str_type=False):\n    try:\n        if to_native_str_type:\n            robotstxt_body = to_unicode(robotstxt_body)\n        else:\n            robotstxt_body = robotstxt_body.decode(\"utf-8\")\n    except UnicodeDecodeError:\n        # If we found garbage or robots.txt in an encoding other than UTF-8, disregard it.\n        # Switch to 'allow all' state.\n        logger.warning(\n            \"Failure while parsing robots.txt. File either contains garbage or \"\n            \"is in an encoding other than UTF-8, treating it as an empty file.\",\n            exc_info=sys.exc_info(),\n            extra={\"spider\": spider},\n        )\n        robotstxt_body = \"\"\n    return robotstxt_body\n\n\nclass RobotParser(metaclass=ABCMeta):\n    @classmethod\n    @abstractmethod\n    def from_crawler(cls, crawler, robotstxt_body):\n        \"\"\"Parse the content of a robots.txt_ file as bytes. This must be a class method.\n        It must return a new instance of the parser backend.\n\n        :param crawler: crawler which made the request\n        :type crawler: :class:`~scrapy.crawler.Crawler` instance\n\n        :param robotstxt_body: content of a robots.txt_ file.\n        :type robotstxt_body: bytes\n        \"\"\"\n        pass\n\n    @abstractmethod\n    def allowed(self, url, user_agent):\n        \"\"\"Return ``True`` if  ``user_agent`` is allowed to crawl ``url``, otherwise return ``False``.\n\n        :param url: Absolute URL\n        :type url: str\n\n        :param user_agent: User agent\n        :type user_agent: str\n        \"\"\"\n        pass\n\n\nclass PythonRobotParser(RobotParser):\n    def __init__(self, robotstxt_body, spider):\n        from urllib.robotparser import RobotFileParser\n\n        self.spider = spider\n        robotstxt_body = decode_robotstxt(\n            robotstxt_body, spider, to_native_str_type=True\n        )\n        self.rp = RobotFileParser()\n        self.rp.parse(robotstxt_body.splitlines())\n\n    @classmethod\n    def from_crawler(cls, crawler, robotstxt_body):\n        spider = None if not crawler else crawler.spider\n        o = cls(robotstxt_body, spider)\n        return o\n\n    def allowed(self, url, user_agent):\n        user_agent = to_unicode(user_agent)\n        url = to_unicode(url)\n        return self.rp.can_fetch(user_agent, url)\n\n\nclass ReppyRobotParser(RobotParser):\n    def __init__(self, robotstxt_body, spider):\n        warn(\"ReppyRobotParser is deprecated.\", ScrapyDeprecationWarning, stacklevel=2)\n        from reppy.robots import Robots\n\n        self.spider = spider\n        self.rp = Robots.parse(\"\", robotstxt_body)\n\n    @classmethod\n    def from_crawler(cls, crawler, robotstxt_body):\n        spider = None if not crawler else crawler.spider\n        o = cls(robotstxt_body, spider)\n        return o\n\n    def allowed(self, url, user_agent):\n        return self.rp.allowed(url, user_agent)\n\n\nclass RerpRobotParser(RobotParser):\n    def __init__(self, robotstxt_body, spider):\n        from robotexclusionrulesparser import RobotExclusionRulesParser\n\n        self.spider = spider\n        self.rp = RobotExclusionRulesParser()\n        robotstxt_body = decode_robotstxt(robotstxt_body, spider)\n        self.rp.parse(robotstxt_body)\n\n    @classmethod\n    def from_crawler(cls, crawler, robotstxt_body):\n        spider = None if not crawler else crawler.spider\n        o = cls(robotstxt_body, spider)\n        return o\n\n    def allowed(self, url, user_agent):\n        user_agent = to_unicode(user_agent)\n        url = to_unicode(url)\n        return self.rp.is_allowed(user_agent, url)\n\n\nclass ProtegoRobotParser(RobotParser):\n    def __init__(self, robotstxt_body, spider):\n        from protego import Protego\n\n        self.spider = spider\n        robotstxt_body = decode_robotstxt(robotstxt_body, spider)\n        self.rp = Protego.parse(robotstxt_body)\n\n    @classmethod\n    def from_crawler(cls, crawler, robotstxt_body):\n        spider = None if not crawler else crawler.spider\n        o = cls(robotstxt_body, spider)\n        return o\n\n    def allowed(self, url, user_agent):\n        user_agent = to_unicode(user_agent)\n        url = to_unicode(url)\n        return self.rp.can_fetch(url, user_agent)\n", "path": "scrapy/robotstxt.py"}]}