We are currently solving the following issue within our repository. Here is the issue text:
--- BEGIN ISSUE ---
Binding.is_avaialble can print to stderr
Specifically it'll print an error message, you can see this if you run `tests/hazmat/bindings/test_bindings.py`


--- END ISSUE ---

Below are some code segments, each from a relevant file. One or more of these files may contain bugs.
--- BEGIN FILES ---
Path: `cryptography/hazmat/bindings/openssl/binding.py`
Content:
```
1 # Licensed under the Apache License, Version 2.0 (the "License");
2 # you may not use this file except in compliance with the License.
3 # You may obtain a copy of the License at
4 #
5 #    http://www.apache.org/licenses/LICENSE-2.0
6 #
7 # Unless required by applicable law or agreed to in writing, software
8 # distributed under the License is distributed on an "AS IS" BASIS,
9 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
10 # implied.
11 # See the License for the specific language governing permissions and
12 # limitations under the License.
13 
14 from __future__ import absolute_import, division, print_function
15 
16 from cryptography.hazmat.bindings.utils import (
17     build_ffi, binding_available
18 )
19 
20 _OSX_PRE_INCLUDE = """
21 #ifdef __APPLE__
22 #include <AvailabilityMacros.h>
23 #define __ORIG_DEPRECATED_IN_MAC_OS_X_VERSION_10_7_AND_LATER \
24     DEPRECATED_IN_MAC_OS_X_VERSION_10_7_AND_LATER
25 #undef DEPRECATED_IN_MAC_OS_X_VERSION_10_7_AND_LATER
26 #define DEPRECATED_IN_MAC_OS_X_VERSION_10_7_AND_LATER
27 #endif
28 """
29 
30 _OSX_POST_INCLUDE = """
31 #ifdef __APPLE__
32 #undef DEPRECATED_IN_MAC_OS_X_VERSION_10_7_AND_LATER
33 #define DEPRECATED_IN_MAC_OS_X_VERSION_10_7_AND_LATER \
34     __ORIG_DEPRECATED_IN_MAC_OS_X_VERSION_10_7_AND_LATER
35 #endif
36 """
37 
38 
39 class Binding(object):
40     """
41     OpenSSL API wrapper.
42     """
43     _module_prefix = "cryptography.hazmat.bindings.openssl."
44     _modules = [
45         "asn1",
46         "bignum",
47         "bio",
48         "conf",
49         "crypto",
50         "dh",
51         "dsa",
52         "engine",
53         "err",
54         "evp",
55         "hmac",
56         "nid",
57         "objects",
58         "opensslv",
59         "pem",
60         "pkcs7",
61         "pkcs12",
62         "rand",
63         "rsa",
64         "ssl",
65         "x509",
66         "x509name",
67         "x509v3",
68     ]
69 
70     ffi = None
71     lib = None
72 
73     def __init__(self):
74         self._ensure_ffi_initialized()
75 
76     @classmethod
77     def _ensure_ffi_initialized(cls):
78         if cls.ffi is not None and cls.lib is not None:
79             return
80 
81         cls.ffi, cls.lib = build_ffi(cls._module_prefix, cls._modules,
82                                      _OSX_PRE_INCLUDE, _OSX_POST_INCLUDE,
83                                      ["crypto", "ssl"])
84 
85     @classmethod
86     def is_available(cls):
87         return binding_available(cls._ensure_ffi_initialized)
88
```

Path: `cryptography/hazmat/bindings/utils.py`
Content:
```
1 # Licensed under the Apache License, Version 2.0 (the "License");
2 # you may not use this file except in compliance with the License.
3 # You may obtain a copy of the License at
4 #
5 #    http://www.apache.org/licenses/LICENSE-2.0
6 #
7 # Unless required by applicable law or agreed to in writing, software
8 # distributed under the License is distributed on an "AS IS" BASIS,
9 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
10 # implied.
11 # See the License for the specific language governing permissions and
12 # limitations under the License.
13 
14 from __future__ import absolute_import, division, print_function
15 
16 import sys
17 
18 import cffi
19 
20 
21 def build_ffi(module_prefix, modules, pre_include, post_include, libraries):
22     """
23     Modules listed in ``modules`` should have the following attributes:
24 
25     * ``INCLUDES``: A string containing C includes.
26     * ``TYPES``: A string containing C declarations for types.
27     * ``FUNCTIONS``: A string containing C declarations for functions.
28     * ``MACROS``: A string containing C declarations for any macros.
29     * ``CUSTOMIZATIONS``: A string containing arbitrary top-level C code, this
30         can be used to do things like test for a define and provide an
31         alternate implementation based on that.
32     * ``CONDITIONAL_NAMES``: A dict mapping strings of condition names from the
33         library to a list of names which will not be present without the
34         condition.
35     """
36     ffi = cffi.FFI()
37     includes = []
38     functions = []
39     macros = []
40     customizations = []
41     for name in modules:
42         module_name = module_prefix + name
43         __import__(module_name)
44         module = sys.modules[module_name]
45 
46         ffi.cdef(module.TYPES)
47 
48         macros.append(module.MACROS)
49         functions.append(module.FUNCTIONS)
50         includes.append(module.INCLUDES)
51         customizations.append(module.CUSTOMIZATIONS)
52 
53     # loop over the functions & macros after declaring all the types
54     # so we can set interdependent types in different files and still
55     # have them all defined before we parse the funcs & macros
56     for func in functions:
57         ffi.cdef(func)
58     for macro in macros:
59         ffi.cdef(macro)
60 
61     # We include functions here so that if we got any of their definitions
62     # wrong, the underlying C compiler will explode. In C you are allowed
63     # to re-declare a function if it has the same signature. That is:
64     #   int foo(int);
65     #   int foo(int);
66     # is legal, but the following will fail to compile:
67     #   int foo(int);
68     #   int foo(short);
69     lib = ffi.verify(
70         source="\n".join(
71             [pre_include] +
72             includes +
73             [post_include] +
74             functions +
75             customizations
76         ),
77         libraries=libraries,
78         ext_package="cryptography",
79     )
80 
81     for name in modules:
82         module_name = module_prefix + name
83         module = sys.modules[module_name]
84         for condition, names in module.CONDITIONAL_NAMES.items():
85             if not getattr(lib, condition):
86                 for name in names:
87                     delattr(lib, name)
88 
89     return ffi, lib
90 
91 
92 def binding_available(initializer):
93     try:
94         initializer()
95         return True
96     except cffi.VerificationError:
97         return False
98
```
--- 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/cryptography/hazmat/bindings/openssl/binding.py b/cryptography/hazmat/bindings/openssl/binding.py
--- a/cryptography/hazmat/bindings/openssl/binding.py
+++ b/cryptography/hazmat/bindings/openssl/binding.py
@@ -13,9 +13,8 @@
 
 from __future__ import absolute_import, division, print_function
 
-from cryptography.hazmat.bindings.utils import (
-    build_ffi, binding_available
-)
+from cryptography.hazmat.bindings.utils import build_ffi
+
 
 _OSX_PRE_INCLUDE = """
 #ifdef __APPLE__
@@ -84,4 +83,5 @@
 
     @classmethod
     def is_available(cls):
-        return binding_available(cls._ensure_ffi_initialized)
+        # OpenSSL is the only binding so for now it must always be available
+        return True
diff --git a/cryptography/hazmat/bindings/utils.py b/cryptography/hazmat/bindings/utils.py
--- a/cryptography/hazmat/bindings/utils.py
+++ b/cryptography/hazmat/bindings/utils.py
@@ -87,11 +87,3 @@
                     delattr(lib, name)
 
     return ffi, lib
-
-
-def binding_available(initializer):
-    try:
-        initializer()
-        return True
-    except cffi.VerificationError:
-        return False

{"golden_diff": "diff --git a/cryptography/hazmat/bindings/openssl/binding.py b/cryptography/hazmat/bindings/openssl/binding.py\n--- a/cryptography/hazmat/bindings/openssl/binding.py\n+++ b/cryptography/hazmat/bindings/openssl/binding.py\n@@ -13,9 +13,8 @@\n \n from __future__ import absolute_import, division, print_function\n \n-from cryptography.hazmat.bindings.utils import (\n-    build_ffi, binding_available\n-)\n+from cryptography.hazmat.bindings.utils import build_ffi\n+\n \n _OSX_PRE_INCLUDE = \"\"\"\n #ifdef __APPLE__\n@@ -84,4 +83,5 @@\n \n     @classmethod\n     def is_available(cls):\n-        return binding_available(cls._ensure_ffi_initialized)\n+        # OpenSSL is the only binding so for now it must always be available\n+        return True\ndiff --git a/cryptography/hazmat/bindings/utils.py b/cryptography/hazmat/bindings/utils.py\n--- a/cryptography/hazmat/bindings/utils.py\n+++ b/cryptography/hazmat/bindings/utils.py\n@@ -87,11 +87,3 @@\n                     delattr(lib, name)\n \n     return ffi, lib\n-\n-\n-def binding_available(initializer):\n-    try:\n-        initializer()\n-        return True\n-    except cffi.VerificationError:\n-        return False\n", "issue": "Binding.is_avaialble can print to stderr\nSpecifically it'll print an error message, you can see this if you run `tests/hazmat/bindings/test_bindings.py`\n\n", "before_files": [{"content": "# Licensed under the Apache License, Version 2.0 (the \"License\");\n# you may not use this file except in compliance with the License.\n# You may obtain a copy of the License at\n#\n#    http://www.apache.org/licenses/LICENSE-2.0\n#\n# Unless required by applicable law or agreed to in writing, software\n# distributed under the License is distributed on an \"AS IS\" BASIS,\n# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or\n# implied.\n# See the License for the specific language governing permissions and\n# limitations under the License.\n\nfrom __future__ import absolute_import, division, print_function\n\nfrom cryptography.hazmat.bindings.utils import (\n    build_ffi, binding_available\n)\n\n_OSX_PRE_INCLUDE = \"\"\"\n#ifdef __APPLE__\n#include <AvailabilityMacros.h>\n#define __ORIG_DEPRECATED_IN_MAC_OS_X_VERSION_10_7_AND_LATER \\\n    DEPRECATED_IN_MAC_OS_X_VERSION_10_7_AND_LATER\n#undef DEPRECATED_IN_MAC_OS_X_VERSION_10_7_AND_LATER\n#define DEPRECATED_IN_MAC_OS_X_VERSION_10_7_AND_LATER\n#endif\n\"\"\"\n\n_OSX_POST_INCLUDE = \"\"\"\n#ifdef __APPLE__\n#undef DEPRECATED_IN_MAC_OS_X_VERSION_10_7_AND_LATER\n#define DEPRECATED_IN_MAC_OS_X_VERSION_10_7_AND_LATER \\\n    __ORIG_DEPRECATED_IN_MAC_OS_X_VERSION_10_7_AND_LATER\n#endif\n\"\"\"\n\n\nclass Binding(object):\n    \"\"\"\n    OpenSSL API wrapper.\n    \"\"\"\n    _module_prefix = \"cryptography.hazmat.bindings.openssl.\"\n    _modules = [\n        \"asn1\",\n        \"bignum\",\n        \"bio\",\n        \"conf\",\n        \"crypto\",\n        \"dh\",\n        \"dsa\",\n        \"engine\",\n        \"err\",\n        \"evp\",\n        \"hmac\",\n        \"nid\",\n        \"objects\",\n        \"opensslv\",\n        \"pem\",\n        \"pkcs7\",\n        \"pkcs12\",\n        \"rand\",\n        \"rsa\",\n        \"ssl\",\n        \"x509\",\n        \"x509name\",\n        \"x509v3\",\n    ]\n\n    ffi = None\n    lib = None\n\n    def __init__(self):\n        self._ensure_ffi_initialized()\n\n    @classmethod\n    def _ensure_ffi_initialized(cls):\n        if cls.ffi is not None and cls.lib is not None:\n            return\n\n        cls.ffi, cls.lib = build_ffi(cls._module_prefix, cls._modules,\n                                     _OSX_PRE_INCLUDE, _OSX_POST_INCLUDE,\n                                     [\"crypto\", \"ssl\"])\n\n    @classmethod\n    def is_available(cls):\n        return binding_available(cls._ensure_ffi_initialized)\n", "path": "cryptography/hazmat/bindings/openssl/binding.py"}, {"content": "# Licensed under the Apache License, Version 2.0 (the \"License\");\n# you may not use this file except in compliance with the License.\n# You may obtain a copy of the License at\n#\n#    http://www.apache.org/licenses/LICENSE-2.0\n#\n# Unless required by applicable law or agreed to in writing, software\n# distributed under the License is distributed on an \"AS IS\" BASIS,\n# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or\n# implied.\n# See the License for the specific language governing permissions and\n# limitations under the License.\n\nfrom __future__ import absolute_import, division, print_function\n\nimport sys\n\nimport cffi\n\n\ndef build_ffi(module_prefix, modules, pre_include, post_include, libraries):\n    \"\"\"\n    Modules listed in ``modules`` should have the following attributes:\n\n    * ``INCLUDES``: A string containing C includes.\n    * ``TYPES``: A string containing C declarations for types.\n    * ``FUNCTIONS``: A string containing C declarations for functions.\n    * ``MACROS``: A string containing C declarations for any macros.\n    * ``CUSTOMIZATIONS``: A string containing arbitrary top-level C code, this\n        can be used to do things like test for a define and provide an\n        alternate implementation based on that.\n    * ``CONDITIONAL_NAMES``: A dict mapping strings of condition names from the\n        library to a list of names which will not be present without the\n        condition.\n    \"\"\"\n    ffi = cffi.FFI()\n    includes = []\n    functions = []\n    macros = []\n    customizations = []\n    for name in modules:\n        module_name = module_prefix + name\n        __import__(module_name)\n        module = sys.modules[module_name]\n\n        ffi.cdef(module.TYPES)\n\n        macros.append(module.MACROS)\n        functions.append(module.FUNCTIONS)\n        includes.append(module.INCLUDES)\n        customizations.append(module.CUSTOMIZATIONS)\n\n    # loop over the functions & macros after declaring all the types\n    # so we can set interdependent types in different files and still\n    # have them all defined before we parse the funcs & macros\n    for func in functions:\n        ffi.cdef(func)\n    for macro in macros:\n        ffi.cdef(macro)\n\n    # We include functions here so that if we got any of their definitions\n    # wrong, the underlying C compiler will explode. In C you are allowed\n    # to re-declare a function if it has the same signature. That is:\n    #   int foo(int);\n    #   int foo(int);\n    # is legal, but the following will fail to compile:\n    #   int foo(int);\n    #   int foo(short);\n    lib = ffi.verify(\n        source=\"\\n\".join(\n            [pre_include] +\n            includes +\n            [post_include] +\n            functions +\n            customizations\n        ),\n        libraries=libraries,\n        ext_package=\"cryptography\",\n    )\n\n    for name in modules:\n        module_name = module_prefix + name\n        module = sys.modules[module_name]\n        for condition, names in module.CONDITIONAL_NAMES.items():\n            if not getattr(lib, condition):\n                for name in names:\n                    delattr(lib, name)\n\n    return ffi, lib\n\n\ndef binding_available(initializer):\n    try:\n        initializer()\n        return True\n    except cffi.VerificationError:\n        return False\n", "path": "cryptography/hazmat/bindings/utils.py"}], "after_files": [{"content": "# Licensed under the Apache License, Version 2.0 (the \"License\");\n# you may not use this file except in compliance with the License.\n# You may obtain a copy of the License at\n#\n#    http://www.apache.org/licenses/LICENSE-2.0\n#\n# Unless required by applicable law or agreed to in writing, software\n# distributed under the License is distributed on an \"AS IS\" BASIS,\n# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or\n# implied.\n# See the License for the specific language governing permissions and\n# limitations under the License.\n\nfrom __future__ import absolute_import, division, print_function\n\nfrom cryptography.hazmat.bindings.utils import build_ffi\n\n\n_OSX_PRE_INCLUDE = \"\"\"\n#ifdef __APPLE__\n#include <AvailabilityMacros.h>\n#define __ORIG_DEPRECATED_IN_MAC_OS_X_VERSION_10_7_AND_LATER \\\n    DEPRECATED_IN_MAC_OS_X_VERSION_10_7_AND_LATER\n#undef DEPRECATED_IN_MAC_OS_X_VERSION_10_7_AND_LATER\n#define DEPRECATED_IN_MAC_OS_X_VERSION_10_7_AND_LATER\n#endif\n\"\"\"\n\n_OSX_POST_INCLUDE = \"\"\"\n#ifdef __APPLE__\n#undef DEPRECATED_IN_MAC_OS_X_VERSION_10_7_AND_LATER\n#define DEPRECATED_IN_MAC_OS_X_VERSION_10_7_AND_LATER \\\n    __ORIG_DEPRECATED_IN_MAC_OS_X_VERSION_10_7_AND_LATER\n#endif\n\"\"\"\n\n\nclass Binding(object):\n    \"\"\"\n    OpenSSL API wrapper.\n    \"\"\"\n    _module_prefix = \"cryptography.hazmat.bindings.openssl.\"\n    _modules = [\n        \"asn1\",\n        \"bignum\",\n        \"bio\",\n        \"conf\",\n        \"crypto\",\n        \"dh\",\n        \"dsa\",\n        \"engine\",\n        \"err\",\n        \"evp\",\n        \"hmac\",\n        \"nid\",\n        \"objects\",\n        \"opensslv\",\n        \"pem\",\n        \"pkcs7\",\n        \"pkcs12\",\n        \"rand\",\n        \"rsa\",\n        \"ssl\",\n        \"x509\",\n        \"x509name\",\n        \"x509v3\",\n    ]\n\n    ffi = None\n    lib = None\n\n    def __init__(self):\n        self._ensure_ffi_initialized()\n\n    @classmethod\n    def _ensure_ffi_initialized(cls):\n        if cls.ffi is not None and cls.lib is not None:\n            return\n\n        cls.ffi, cls.lib = build_ffi(cls._module_prefix, cls._modules,\n                                     _OSX_PRE_INCLUDE, _OSX_POST_INCLUDE,\n                                     [\"crypto\", \"ssl\"])\n\n    @classmethod\n    def is_available(cls):\n        # OpenSSL is the only binding so for now it must always be available\n        return True\n", "path": "cryptography/hazmat/bindings/openssl/binding.py"}, {"content": "# Licensed under the Apache License, Version 2.0 (the \"License\");\n# you may not use this file except in compliance with the License.\n# You may obtain a copy of the License at\n#\n#    http://www.apache.org/licenses/LICENSE-2.0\n#\n# Unless required by applicable law or agreed to in writing, software\n# distributed under the License is distributed on an \"AS IS\" BASIS,\n# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or\n# implied.\n# See the License for the specific language governing permissions and\n# limitations under the License.\n\nfrom __future__ import absolute_import, division, print_function\n\nimport sys\n\nimport cffi\n\n\ndef build_ffi(module_prefix, modules, pre_include, post_include, libraries):\n    \"\"\"\n    Modules listed in ``modules`` should have the following attributes:\n\n    * ``INCLUDES``: A string containing C includes.\n    * ``TYPES``: A string containing C declarations for types.\n    * ``FUNCTIONS``: A string containing C declarations for functions.\n    * ``MACROS``: A string containing C declarations for any macros.\n    * ``CUSTOMIZATIONS``: A string containing arbitrary top-level C code, this\n        can be used to do things like test for a define and provide an\n        alternate implementation based on that.\n    * ``CONDITIONAL_NAMES``: A dict mapping strings of condition names from the\n        library to a list of names which will not be present without the\n        condition.\n    \"\"\"\n    ffi = cffi.FFI()\n    includes = []\n    functions = []\n    macros = []\n    customizations = []\n    for name in modules:\n        module_name = module_prefix + name\n        __import__(module_name)\n        module = sys.modules[module_name]\n\n        ffi.cdef(module.TYPES)\n\n        macros.append(module.MACROS)\n        functions.append(module.FUNCTIONS)\n        includes.append(module.INCLUDES)\n        customizations.append(module.CUSTOMIZATIONS)\n\n    # loop over the functions & macros after declaring all the types\n    # so we can set interdependent types in different files and still\n    # have them all defined before we parse the funcs & macros\n    for func in functions:\n        ffi.cdef(func)\n    for macro in macros:\n        ffi.cdef(macro)\n\n    # We include functions here so that if we got any of their definitions\n    # wrong, the underlying C compiler will explode. In C you are allowed\n    # to re-declare a function if it has the same signature. That is:\n    #   int foo(int);\n    #   int foo(int);\n    # is legal, but the following will fail to compile:\n    #   int foo(int);\n    #   int foo(short);\n    lib = ffi.verify(\n        source=\"\\n\".join(\n            [pre_include] +\n            includes +\n            [post_include] +\n            functions +\n            customizations\n        ),\n        libraries=libraries,\n        ext_package=\"cryptography\",\n    )\n\n    for name in modules:\n        module_name = module_prefix + name\n        module = sys.modules[module_name]\n        for condition, names in module.CONDITIONAL_NAMES.items():\n            if not getattr(lib, condition):\n                for name in names:\n                    delattr(lib, name)\n\n    return ffi, lib\n", "path": "cryptography/hazmat/bindings/utils.py"}]}