We are currently solving the following issue within our repository. Here is the issue text:
--- BEGIN ISSUE ---
DHParametersWithSerialization, DHPublicKeyWithSerialization
For RSAPublicKey, DSAPublicKey, and EllipticCurvePublicKey we decided that there was no scenario under which they could not be serializable. The same is true for these two classes, so we should go ahead and merge the interfaces and then make the WithSerialization versions aliases (this is the approach we took for the other 3 to maintain backwards compatibility)
DHParametersWithSerialization, DHPublicKeyWithSerialization
For RSAPublicKey, DSAPublicKey, and EllipticCurvePublicKey we decided that there was no scenario under which they could not be serializable. The same is true for these two classes, so we should go ahead and merge the interfaces and then make the WithSerialization versions aliases (this is the approach we took for the other 3 to maintain backwards compatibility)

--- END ISSUE ---

Below are some code segments, each from a relevant file. One or more of these files may contain bugs.
--- BEGIN FILES ---
Path: `src/cryptography/hazmat/primitives/asymmetric/dh.py`
Content:
```
1 # This file is dual licensed under the terms of the Apache License, Version
2 # 2.0, and the BSD License. See the LICENSE file in the root of this repository
3 # for complete details.
4 
5 from __future__ import absolute_import, division, print_function
6 
7 import abc
8 
9 import six
10 
11 from cryptography import utils
12 
13 
14 def generate_parameters(generator, key_size, backend):
15     return backend.generate_dh_parameters(generator, key_size)
16 
17 
18 class DHPrivateNumbers(object):
19     def __init__(self, x, public_numbers):
20         if not isinstance(x, six.integer_types):
21             raise TypeError("x must be an integer.")
22 
23         if not isinstance(public_numbers, DHPublicNumbers):
24             raise TypeError("public_numbers must be an instance of "
25                             "DHPublicNumbers.")
26 
27         self._x = x
28         self._public_numbers = public_numbers
29 
30     def __eq__(self, other):
31         if not isinstance(other, DHPrivateNumbers):
32             return NotImplemented
33 
34         return (
35             self._x == other._x and
36             self._public_numbers == other._public_numbers
37         )
38 
39     def __ne__(self, other):
40         return not self == other
41 
42     def private_key(self, backend):
43         return backend.load_dh_private_numbers(self)
44 
45     public_numbers = utils.read_only_property("_public_numbers")
46     x = utils.read_only_property("_x")
47 
48 
49 class DHPublicNumbers(object):
50     def __init__(self, y, parameter_numbers):
51         if not isinstance(y, six.integer_types):
52             raise TypeError("y must be an integer.")
53 
54         if not isinstance(parameter_numbers, DHParameterNumbers):
55             raise TypeError(
56                 "parameters must be an instance of DHParameterNumbers.")
57 
58         self._y = y
59         self._parameter_numbers = parameter_numbers
60 
61     def __eq__(self, other):
62         if not isinstance(other, DHPublicNumbers):
63             return NotImplemented
64 
65         return (
66             self._y == other._y and
67             self._parameter_numbers == other._parameter_numbers
68         )
69 
70     def __ne__(self, other):
71         return not self == other
72 
73     def public_key(self, backend):
74         return backend.load_dh_public_numbers(self)
75 
76     y = utils.read_only_property("_y")
77     parameter_numbers = utils.read_only_property("_parameter_numbers")
78 
79 
80 class DHParameterNumbers(object):
81     def __init__(self, p, g, q=None):
82         if (
83             not isinstance(p, six.integer_types) or
84             not isinstance(g, six.integer_types)
85         ):
86             raise TypeError("p and g must be integers")
87         if q is not None and not isinstance(q, six.integer_types):
88             raise TypeError("q must be integer or None")
89 
90         if q is None and g not in (2, 5):
91             raise ValueError("DH generator must be 2 or 5")
92 
93         self._p = p
94         self._g = g
95         self._q = q
96 
97     def __eq__(self, other):
98         if not isinstance(other, DHParameterNumbers):
99             return NotImplemented
100 
101         return (
102             self._p == other._p and
103             self._g == other._g and
104             self._q == other._q
105         )
106 
107     def __ne__(self, other):
108         return not self == other
109 
110     def parameters(self, backend):
111         return backend.load_dh_parameter_numbers(self)
112 
113     p = utils.read_only_property("_p")
114     g = utils.read_only_property("_g")
115     q = utils.read_only_property("_q")
116 
117 
118 @six.add_metaclass(abc.ABCMeta)
119 class DHParameters(object):
120     @abc.abstractmethod
121     def generate_private_key(self):
122         """
123         Generates and returns a DHPrivateKey.
124         """
125 
126     @abc.abstractmethod
127     def parameter_bytes(self, encoding, format):
128         """
129         Returns the parameters serialized as bytes.
130         """
131 
132 
133 @six.add_metaclass(abc.ABCMeta)
134 class DHParametersWithSerialization(DHParameters):
135     @abc.abstractmethod
136     def parameter_numbers(self):
137         """
138         Returns a DHParameterNumbers.
139         """
140 
141 
142 @six.add_metaclass(abc.ABCMeta)
143 class DHPrivateKey(object):
144     @abc.abstractproperty
145     def key_size(self):
146         """
147         The bit length of the prime modulus.
148         """
149 
150     @abc.abstractmethod
151     def public_key(self):
152         """
153         The DHPublicKey associated with this private key.
154         """
155 
156     @abc.abstractmethod
157     def parameters(self):
158         """
159         The DHParameters object associated with this private key.
160         """
161 
162     @abc.abstractmethod
163     def exchange(self, peer_public_key):
164         """
165         Given peer's DHPublicKey, carry out the key exchange and
166         return shared key as bytes.
167         """
168 
169 
170 @six.add_metaclass(abc.ABCMeta)
171 class DHPrivateKeyWithSerialization(DHPrivateKey):
172     @abc.abstractmethod
173     def private_numbers(self):
174         """
175         Returns a DHPrivateNumbers.
176         """
177 
178     @abc.abstractmethod
179     def private_bytes(self, encoding, format, encryption_algorithm):
180         """
181         Returns the key serialized as bytes.
182         """
183 
184 
185 @six.add_metaclass(abc.ABCMeta)
186 class DHPublicKey(object):
187     @abc.abstractproperty
188     def key_size(self):
189         """
190         The bit length of the prime modulus.
191         """
192 
193     @abc.abstractmethod
194     def parameters(self):
195         """
196         The DHParameters object associated with this public key.
197         """
198 
199 
200 @six.add_metaclass(abc.ABCMeta)
201 class DHPublicKeyWithSerialization(DHPublicKey):
202     @abc.abstractmethod
203     def public_numbers(self):
204         """
205         Returns a DHPublicNumbers.
206         """
207 
208     @abc.abstractmethod
209     def public_bytes(self, encoding, format):
210         """
211         Returns the key serialized as bytes.
212         """
213
```
--- 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/src/cryptography/hazmat/primitives/asymmetric/dh.py b/src/cryptography/hazmat/primitives/asymmetric/dh.py
--- a/src/cryptography/hazmat/primitives/asymmetric/dh.py
+++ b/src/cryptography/hazmat/primitives/asymmetric/dh.py
@@ -129,9 +129,6 @@
         Returns the parameters serialized as bytes.
         """
 
-
-@six.add_metaclass(abc.ABCMeta)
-class DHParametersWithSerialization(DHParameters):
     @abc.abstractmethod
     def parameter_numbers(self):
         """
@@ -139,6 +136,9 @@
         """
 
 
+DHParametersWithSerialization = DHParameters
+
+
 @six.add_metaclass(abc.ABCMeta)
 class DHPrivateKey(object):
     @abc.abstractproperty
@@ -196,9 +196,6 @@
         The DHParameters object associated with this public key.
         """
 
-
-@six.add_metaclass(abc.ABCMeta)
-class DHPublicKeyWithSerialization(DHPublicKey):
     @abc.abstractmethod
     def public_numbers(self):
         """
@@ -210,3 +207,6 @@
         """
         Returns the key serialized as bytes.
         """
+
+
+DHPublicKeyWithSerialization = DHPublicKey

{"golden_diff": "diff --git a/src/cryptography/hazmat/primitives/asymmetric/dh.py b/src/cryptography/hazmat/primitives/asymmetric/dh.py\n--- a/src/cryptography/hazmat/primitives/asymmetric/dh.py\n+++ b/src/cryptography/hazmat/primitives/asymmetric/dh.py\n@@ -129,9 +129,6 @@\n         Returns the parameters serialized as bytes.\n         \"\"\"\n \n-\n-@six.add_metaclass(abc.ABCMeta)\n-class DHParametersWithSerialization(DHParameters):\n     @abc.abstractmethod\n     def parameter_numbers(self):\n         \"\"\"\n@@ -139,6 +136,9 @@\n         \"\"\"\n \n \n+DHParametersWithSerialization = DHParameters\n+\n+\n @six.add_metaclass(abc.ABCMeta)\n class DHPrivateKey(object):\n     @abc.abstractproperty\n@@ -196,9 +196,6 @@\n         The DHParameters object associated with this public key.\n         \"\"\"\n \n-\n-@six.add_metaclass(abc.ABCMeta)\n-class DHPublicKeyWithSerialization(DHPublicKey):\n     @abc.abstractmethod\n     def public_numbers(self):\n         \"\"\"\n@@ -210,3 +207,6 @@\n         \"\"\"\n         Returns the key serialized as bytes.\n         \"\"\"\n+\n+\n+DHPublicKeyWithSerialization = DHPublicKey\n", "issue": "DHParametersWithSerialization, DHPublicKeyWithSerialization\nFor RSAPublicKey, DSAPublicKey, and EllipticCurvePublicKey we decided that there was no scenario under which they could not be serializable. The same is true for these two classes, so we should go ahead and merge the interfaces and then make the WithSerialization versions aliases (this is the approach we took for the other 3 to maintain backwards compatibility)\nDHParametersWithSerialization, DHPublicKeyWithSerialization\nFor RSAPublicKey, DSAPublicKey, and EllipticCurvePublicKey we decided that there was no scenario under which they could not be serializable. The same is true for these two classes, so we should go ahead and merge the interfaces and then make the WithSerialization versions aliases (this is the approach we took for the other 3 to maintain backwards compatibility)\n", "before_files": [{"content": "# This file is dual licensed under the terms of the Apache License, Version\n# 2.0, and the BSD License. See the LICENSE file in the root of this repository\n# for complete details.\n\nfrom __future__ import absolute_import, division, print_function\n\nimport abc\n\nimport six\n\nfrom cryptography import utils\n\n\ndef generate_parameters(generator, key_size, backend):\n    return backend.generate_dh_parameters(generator, key_size)\n\n\nclass DHPrivateNumbers(object):\n    def __init__(self, x, public_numbers):\n        if not isinstance(x, six.integer_types):\n            raise TypeError(\"x must be an integer.\")\n\n        if not isinstance(public_numbers, DHPublicNumbers):\n            raise TypeError(\"public_numbers must be an instance of \"\n                            \"DHPublicNumbers.\")\n\n        self._x = x\n        self._public_numbers = public_numbers\n\n    def __eq__(self, other):\n        if not isinstance(other, DHPrivateNumbers):\n            return NotImplemented\n\n        return (\n            self._x == other._x and\n            self._public_numbers == other._public_numbers\n        )\n\n    def __ne__(self, other):\n        return not self == other\n\n    def private_key(self, backend):\n        return backend.load_dh_private_numbers(self)\n\n    public_numbers = utils.read_only_property(\"_public_numbers\")\n    x = utils.read_only_property(\"_x\")\n\n\nclass DHPublicNumbers(object):\n    def __init__(self, y, parameter_numbers):\n        if not isinstance(y, six.integer_types):\n            raise TypeError(\"y must be an integer.\")\n\n        if not isinstance(parameter_numbers, DHParameterNumbers):\n            raise TypeError(\n                \"parameters must be an instance of DHParameterNumbers.\")\n\n        self._y = y\n        self._parameter_numbers = parameter_numbers\n\n    def __eq__(self, other):\n        if not isinstance(other, DHPublicNumbers):\n            return NotImplemented\n\n        return (\n            self._y == other._y and\n            self._parameter_numbers == other._parameter_numbers\n        )\n\n    def __ne__(self, other):\n        return not self == other\n\n    def public_key(self, backend):\n        return backend.load_dh_public_numbers(self)\n\n    y = utils.read_only_property(\"_y\")\n    parameter_numbers = utils.read_only_property(\"_parameter_numbers\")\n\n\nclass DHParameterNumbers(object):\n    def __init__(self, p, g, q=None):\n        if (\n            not isinstance(p, six.integer_types) or\n            not isinstance(g, six.integer_types)\n        ):\n            raise TypeError(\"p and g must be integers\")\n        if q is not None and not isinstance(q, six.integer_types):\n            raise TypeError(\"q must be integer or None\")\n\n        if q is None and g not in (2, 5):\n            raise ValueError(\"DH generator must be 2 or 5\")\n\n        self._p = p\n        self._g = g\n        self._q = q\n\n    def __eq__(self, other):\n        if not isinstance(other, DHParameterNumbers):\n            return NotImplemented\n\n        return (\n            self._p == other._p and\n            self._g == other._g and\n            self._q == other._q\n        )\n\n    def __ne__(self, other):\n        return not self == other\n\n    def parameters(self, backend):\n        return backend.load_dh_parameter_numbers(self)\n\n    p = utils.read_only_property(\"_p\")\n    g = utils.read_only_property(\"_g\")\n    q = utils.read_only_property(\"_q\")\n\n\n@six.add_metaclass(abc.ABCMeta)\nclass DHParameters(object):\n    @abc.abstractmethod\n    def generate_private_key(self):\n        \"\"\"\n        Generates and returns a DHPrivateKey.\n        \"\"\"\n\n    @abc.abstractmethod\n    def parameter_bytes(self, encoding, format):\n        \"\"\"\n        Returns the parameters serialized as bytes.\n        \"\"\"\n\n\n@six.add_metaclass(abc.ABCMeta)\nclass DHParametersWithSerialization(DHParameters):\n    @abc.abstractmethod\n    def parameter_numbers(self):\n        \"\"\"\n        Returns a DHParameterNumbers.\n        \"\"\"\n\n\n@six.add_metaclass(abc.ABCMeta)\nclass DHPrivateKey(object):\n    @abc.abstractproperty\n    def key_size(self):\n        \"\"\"\n        The bit length of the prime modulus.\n        \"\"\"\n\n    @abc.abstractmethod\n    def public_key(self):\n        \"\"\"\n        The DHPublicKey associated with this private key.\n        \"\"\"\n\n    @abc.abstractmethod\n    def parameters(self):\n        \"\"\"\n        The DHParameters object associated with this private key.\n        \"\"\"\n\n    @abc.abstractmethod\n    def exchange(self, peer_public_key):\n        \"\"\"\n        Given peer's DHPublicKey, carry out the key exchange and\n        return shared key as bytes.\n        \"\"\"\n\n\n@six.add_metaclass(abc.ABCMeta)\nclass DHPrivateKeyWithSerialization(DHPrivateKey):\n    @abc.abstractmethod\n    def private_numbers(self):\n        \"\"\"\n        Returns a DHPrivateNumbers.\n        \"\"\"\n\n    @abc.abstractmethod\n    def private_bytes(self, encoding, format, encryption_algorithm):\n        \"\"\"\n        Returns the key serialized as bytes.\n        \"\"\"\n\n\n@six.add_metaclass(abc.ABCMeta)\nclass DHPublicKey(object):\n    @abc.abstractproperty\n    def key_size(self):\n        \"\"\"\n        The bit length of the prime modulus.\n        \"\"\"\n\n    @abc.abstractmethod\n    def parameters(self):\n        \"\"\"\n        The DHParameters object associated with this public key.\n        \"\"\"\n\n\n@six.add_metaclass(abc.ABCMeta)\nclass DHPublicKeyWithSerialization(DHPublicKey):\n    @abc.abstractmethod\n    def public_numbers(self):\n        \"\"\"\n        Returns a DHPublicNumbers.\n        \"\"\"\n\n    @abc.abstractmethod\n    def public_bytes(self, encoding, format):\n        \"\"\"\n        Returns the key serialized as bytes.\n        \"\"\"\n", "path": "src/cryptography/hazmat/primitives/asymmetric/dh.py"}], "after_files": [{"content": "# This file is dual licensed under the terms of the Apache License, Version\n# 2.0, and the BSD License. See the LICENSE file in the root of this repository\n# for complete details.\n\nfrom __future__ import absolute_import, division, print_function\n\nimport abc\n\nimport six\n\nfrom cryptography import utils\n\n\ndef generate_parameters(generator, key_size, backend):\n    return backend.generate_dh_parameters(generator, key_size)\n\n\nclass DHPrivateNumbers(object):\n    def __init__(self, x, public_numbers):\n        if not isinstance(x, six.integer_types):\n            raise TypeError(\"x must be an integer.\")\n\n        if not isinstance(public_numbers, DHPublicNumbers):\n            raise TypeError(\"public_numbers must be an instance of \"\n                            \"DHPublicNumbers.\")\n\n        self._x = x\n        self._public_numbers = public_numbers\n\n    def __eq__(self, other):\n        if not isinstance(other, DHPrivateNumbers):\n            return NotImplemented\n\n        return (\n            self._x == other._x and\n            self._public_numbers == other._public_numbers\n        )\n\n    def __ne__(self, other):\n        return not self == other\n\n    def private_key(self, backend):\n        return backend.load_dh_private_numbers(self)\n\n    public_numbers = utils.read_only_property(\"_public_numbers\")\n    x = utils.read_only_property(\"_x\")\n\n\nclass DHPublicNumbers(object):\n    def __init__(self, y, parameter_numbers):\n        if not isinstance(y, six.integer_types):\n            raise TypeError(\"y must be an integer.\")\n\n        if not isinstance(parameter_numbers, DHParameterNumbers):\n            raise TypeError(\n                \"parameters must be an instance of DHParameterNumbers.\")\n\n        self._y = y\n        self._parameter_numbers = parameter_numbers\n\n    def __eq__(self, other):\n        if not isinstance(other, DHPublicNumbers):\n            return NotImplemented\n\n        return (\n            self._y == other._y and\n            self._parameter_numbers == other._parameter_numbers\n        )\n\n    def __ne__(self, other):\n        return not self == other\n\n    def public_key(self, backend):\n        return backend.load_dh_public_numbers(self)\n\n    y = utils.read_only_property(\"_y\")\n    parameter_numbers = utils.read_only_property(\"_parameter_numbers\")\n\n\nclass DHParameterNumbers(object):\n    def __init__(self, p, g, q=None):\n        if (\n            not isinstance(p, six.integer_types) or\n            not isinstance(g, six.integer_types)\n        ):\n            raise TypeError(\"p and g must be integers\")\n        if q is not None and not isinstance(q, six.integer_types):\n            raise TypeError(\"q must be integer or None\")\n\n        if q is None and g not in (2, 5):\n            raise ValueError(\"DH generator must be 2 or 5\")\n\n        self._p = p\n        self._g = g\n        self._q = q\n\n    def __eq__(self, other):\n        if not isinstance(other, DHParameterNumbers):\n            return NotImplemented\n\n        return (\n            self._p == other._p and\n            self._g == other._g and\n            self._q == other._q\n        )\n\n    def __ne__(self, other):\n        return not self == other\n\n    def parameters(self, backend):\n        return backend.load_dh_parameter_numbers(self)\n\n    p = utils.read_only_property(\"_p\")\n    g = utils.read_only_property(\"_g\")\n    q = utils.read_only_property(\"_q\")\n\n\n@six.add_metaclass(abc.ABCMeta)\nclass DHParameters(object):\n    @abc.abstractmethod\n    def generate_private_key(self):\n        \"\"\"\n        Generates and returns a DHPrivateKey.\n        \"\"\"\n\n    @abc.abstractmethod\n    def parameter_bytes(self, encoding, format):\n        \"\"\"\n        Returns the parameters serialized as bytes.\n        \"\"\"\n\n    @abc.abstractmethod\n    def parameter_numbers(self):\n        \"\"\"\n        Returns a DHParameterNumbers.\n        \"\"\"\n\n\nDHParametersWithSerialization = DHParameters\n\n\n@six.add_metaclass(abc.ABCMeta)\nclass DHPrivateKey(object):\n    @abc.abstractproperty\n    def key_size(self):\n        \"\"\"\n        The bit length of the prime modulus.\n        \"\"\"\n\n    @abc.abstractmethod\n    def public_key(self):\n        \"\"\"\n        The DHPublicKey associated with this private key.\n        \"\"\"\n\n    @abc.abstractmethod\n    def parameters(self):\n        \"\"\"\n        The DHParameters object associated with this private key.\n        \"\"\"\n\n    @abc.abstractmethod\n    def exchange(self, peer_public_key):\n        \"\"\"\n        Given peer's DHPublicKey, carry out the key exchange and\n        return shared key as bytes.\n        \"\"\"\n\n\n@six.add_metaclass(abc.ABCMeta)\nclass DHPrivateKeyWithSerialization(DHPrivateKey):\n    @abc.abstractmethod\n    def private_numbers(self):\n        \"\"\"\n        Returns a DHPrivateNumbers.\n        \"\"\"\n\n    @abc.abstractmethod\n    def private_bytes(self, encoding, format, encryption_algorithm):\n        \"\"\"\n        Returns the key serialized as bytes.\n        \"\"\"\n\n\n@six.add_metaclass(abc.ABCMeta)\nclass DHPublicKey(object):\n    @abc.abstractproperty\n    def key_size(self):\n        \"\"\"\n        The bit length of the prime modulus.\n        \"\"\"\n\n    @abc.abstractmethod\n    def parameters(self):\n        \"\"\"\n        The DHParameters object associated with this public key.\n        \"\"\"\n\n    @abc.abstractmethod\n    def public_numbers(self):\n        \"\"\"\n        Returns a DHPublicNumbers.\n        \"\"\"\n\n    @abc.abstractmethod\n    def public_bytes(self, encoding, format):\n        \"\"\"\n        Returns the key serialized as bytes.\n        \"\"\"\n\n\nDHPublicKeyWithSerialization = DHPublicKey\n", "path": "src/cryptography/hazmat/primitives/asymmetric/dh.py"}]}