We are currently solving the following issue within our repository. Here is the issue text:
--- BEGIN ISSUE ---
Show installed version in command-line
I'd expect `mkdocs help` to display the currently installed version, would be nice to have for the next versions


--- END ISSUE ---

Below are some code segments, each from a relevant file. One or more of these files may contain bugs.
--- BEGIN FILES ---
Path: `mkdocs/main.py`
Content:
```
1 #!/usr/bin/env python
2 # coding: utf-8
3 from __future__ import print_function
4 
5 import sys
6 
7 from mkdocs.build import build
8 from mkdocs.config import load_config
9 from mkdocs.exceptions import ConfigurationError
10 from mkdocs.gh_deploy import gh_deploy
11 from mkdocs.new import new
12 from mkdocs.serve import serve
13 
14 
15 def arg_to_option(arg):
16     """
17     Convert command line arguments into two-tuples of config key/value pairs.
18     """
19     arg = arg.lstrip('--')
20     option = True
21     if '=' in arg:
22         arg, option = arg.split('=', 1)
23     return (arg.replace('-', '_'), option)
24 
25 
26 def main(cmd, args, options=None):
27     """
28     Build the documentation, and optionally start the devserver.
29     """
30     clean_site_dir = 'clean' in options
31     if cmd == 'serve':
32         config = load_config(options=options)
33         serve(config, options=options)
34     elif cmd == 'build':
35         config = load_config(options=options)
36         build(config, clean_site_dir=clean_site_dir)
37     elif cmd == 'json':
38         config = load_config(options=options)
39         build(config, dump_json=True, clean_site_dir=clean_site_dir)
40     elif cmd == 'gh-deploy':
41         config = load_config(options=options)
42         build(config, clean_site_dir=clean_site_dir)
43         gh_deploy(config)
44     elif cmd == 'new':
45         new(args, options)
46     else:
47         print('mkdocs [help|new|build|serve|gh-deploy|json] {options}')
48 
49 
50 def run_main():
51     """
52     Invokes main() with the contents of sys.argv
53 
54     This is a separate function so it can be invoked
55     by a setuptools console_script.
56     """
57     cmd = sys.argv[1] if len(sys.argv) >= 2 else None
58     opts = [arg_to_option(arg) for arg in sys.argv[2:] if arg.startswith('--')]
59     try:
60         main(cmd, args=sys.argv[2:], options=dict(opts))
61     except ConfigurationError as e:
62         print(e.args[0], file=sys.stderr)
63 
64 
65 if __name__ == '__main__':
66     run_main()
67
```
--- 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/mkdocs/main.py b/mkdocs/main.py
--- a/mkdocs/main.py
+++ b/mkdocs/main.py
@@ -4,6 +4,7 @@
 
 import sys
 
+from mkdocs import __version__
 from mkdocs.build import build
 from mkdocs.config import load_config
 from mkdocs.exceptions import ConfigurationError
@@ -44,6 +45,7 @@
     elif cmd == 'new':
         new(args, options)
     else:
+        print('MkDocs (version {0})'.format(__version__))
         print('mkdocs [help|new|build|serve|gh-deploy|json] {options}')

{"golden_diff": "diff --git a/mkdocs/main.py b/mkdocs/main.py\n--- a/mkdocs/main.py\n+++ b/mkdocs/main.py\n@@ -4,6 +4,7 @@\n \n import sys\n \n+from mkdocs import __version__\n from mkdocs.build import build\n from mkdocs.config import load_config\n from mkdocs.exceptions import ConfigurationError\n@@ -44,6 +45,7 @@\n     elif cmd == 'new':\n         new(args, options)\n     else:\n+        print('MkDocs (version {0})'.format(__version__))\n         print('mkdocs [help|new|build|serve|gh-deploy|json] {options}')\n", "issue": "Show installed version in command-line\nI'd expect `mkdocs help` to display the currently installed version, would be nice to have for the next versions\n\n", "before_files": [{"content": "#!/usr/bin/env python\n# coding: utf-8\nfrom __future__ import print_function\n\nimport sys\n\nfrom mkdocs.build import build\nfrom mkdocs.config import load_config\nfrom mkdocs.exceptions import ConfigurationError\nfrom mkdocs.gh_deploy import gh_deploy\nfrom mkdocs.new import new\nfrom mkdocs.serve import serve\n\n\ndef arg_to_option(arg):\n    \"\"\"\n    Convert command line arguments into two-tuples of config key/value pairs.\n    \"\"\"\n    arg = arg.lstrip('--')\n    option = True\n    if '=' in arg:\n        arg, option = arg.split('=', 1)\n    return (arg.replace('-', '_'), option)\n\n\ndef main(cmd, args, options=None):\n    \"\"\"\n    Build the documentation, and optionally start the devserver.\n    \"\"\"\n    clean_site_dir = 'clean' in options\n    if cmd == 'serve':\n        config = load_config(options=options)\n        serve(config, options=options)\n    elif cmd == 'build':\n        config = load_config(options=options)\n        build(config, clean_site_dir=clean_site_dir)\n    elif cmd == 'json':\n        config = load_config(options=options)\n        build(config, dump_json=True, clean_site_dir=clean_site_dir)\n    elif cmd == 'gh-deploy':\n        config = load_config(options=options)\n        build(config, clean_site_dir=clean_site_dir)\n        gh_deploy(config)\n    elif cmd == 'new':\n        new(args, options)\n    else:\n        print('mkdocs [help|new|build|serve|gh-deploy|json] {options}')\n\n\ndef run_main():\n    \"\"\"\n    Invokes main() with the contents of sys.argv\n\n    This is a separate function so it can be invoked\n    by a setuptools console_script.\n    \"\"\"\n    cmd = sys.argv[1] if len(sys.argv) >= 2 else None\n    opts = [arg_to_option(arg) for arg in sys.argv[2:] if arg.startswith('--')]\n    try:\n        main(cmd, args=sys.argv[2:], options=dict(opts))\n    except ConfigurationError as e:\n        print(e.args[0], file=sys.stderr)\n\n\nif __name__ == '__main__':\n    run_main()\n", "path": "mkdocs/main.py"}], "after_files": [{"content": "#!/usr/bin/env python\n# coding: utf-8\nfrom __future__ import print_function\n\nimport sys\n\nfrom mkdocs import __version__\nfrom mkdocs.build import build\nfrom mkdocs.config import load_config\nfrom mkdocs.exceptions import ConfigurationError\nfrom mkdocs.gh_deploy import gh_deploy\nfrom mkdocs.new import new\nfrom mkdocs.serve import serve\n\n\ndef arg_to_option(arg):\n    \"\"\"\n    Convert command line arguments into two-tuples of config key/value pairs.\n    \"\"\"\n    arg = arg.lstrip('--')\n    option = True\n    if '=' in arg:\n        arg, option = arg.split('=', 1)\n    return (arg.replace('-', '_'), option)\n\n\ndef main(cmd, args, options=None):\n    \"\"\"\n    Build the documentation, and optionally start the devserver.\n    \"\"\"\n    clean_site_dir = 'clean' in options\n    if cmd == 'serve':\n        config = load_config(options=options)\n        serve(config, options=options)\n    elif cmd == 'build':\n        config = load_config(options=options)\n        build(config, clean_site_dir=clean_site_dir)\n    elif cmd == 'json':\n        config = load_config(options=options)\n        build(config, dump_json=True, clean_site_dir=clean_site_dir)\n    elif cmd == 'gh-deploy':\n        config = load_config(options=options)\n        build(config, clean_site_dir=clean_site_dir)\n        gh_deploy(config)\n    elif cmd == 'new':\n        new(args, options)\n    else:\n        print('MkDocs (version {0})'.format(__version__))\n        print('mkdocs [help|new|build|serve|gh-deploy|json] {options}')\n\n\ndef run_main():\n    \"\"\"\n    Invokes main() with the contents of sys.argv\n\n    This is a separate function so it can be invoked\n    by a setuptools console_script.\n    \"\"\"\n    cmd = sys.argv[1] if len(sys.argv) >= 2 else None\n    opts = [arg_to_option(arg) for arg in sys.argv[2:] if arg.startswith('--')]\n    try:\n        main(cmd, args=sys.argv[2:], options=dict(opts))\n    except ConfigurationError as e:\n        print(e.args[0], file=sys.stderr)\n\n\nif __name__ == '__main__':\n    run_main()\n", "path": "mkdocs/main.py"}]}