We are currently solving the following issue within our repository. Here is the issue text:
--- BEGIN ISSUE ---
Color regex needs raw string
Warning in CI: 

> bokeh/core/property/color.py:137
  /home/travis/build/bokeh/bokeh/bokeh/core/property/color.py:137: DeprecationWarning: invalid escape sequence \d
    value = colors.RGB(*[int(val) for val in re.findall("\d+", value)[:3]]).to_hex()


--- END ISSUE ---

Below are some code segments, each from a relevant file. One or more of these files may contain bugs.
--- BEGIN FILES ---
Path: `bokeh/core/property/color.py`
Content:
```
1 #-----------------------------------------------------------------------------
2 # Copyright (c) 2012 - 2019, Anaconda, Inc., and Bokeh Contributors.
3 # All rights reserved.
4 #
5 # The full license is in the file LICENSE.txt, distributed with this software.
6 #-----------------------------------------------------------------------------
7 ''' Provide color related properties.
8 
9 '''
10 
11 #-----------------------------------------------------------------------------
12 # Boilerplate
13 #-----------------------------------------------------------------------------
14 from __future__ import absolute_import, division, print_function, unicode_literals
15 
16 import logging
17 log = logging.getLogger(__name__)
18 
19 #-----------------------------------------------------------------------------
20 # Imports
21 #-----------------------------------------------------------------------------
22 
23 # Standard library imports
24 import re
25 
26 # External imports
27 from six import string_types
28 
29 # Bokeh imports
30 from ... import colors
31 from .. import enums
32 from .bases import Property
33 from .container import Tuple
34 from .enum import Enum
35 from .either import Either
36 from .numeric import Byte, Percent
37 from .regex import Regex
38 
39 #-----------------------------------------------------------------------------
40 # Globals and constants
41 #-----------------------------------------------------------------------------
42 
43 __all__ = (
44     'Color',
45     'RGB',
46     'ColorHex',
47 )
48 
49 #-----------------------------------------------------------------------------
50 # General API
51 #-----------------------------------------------------------------------------
52 
53 
54 class RGB(Property):
55     ''' Accept colors.RGB values.
56 
57     '''
58 
59     def validate(self, value, detail=True):
60         super(RGB, self).validate(value, detail)
61 
62         if not (value is None or isinstance(value, colors.RGB)):
63             msg = "" if not detail else "expected RGB value, got %r" % (value,)
64             raise ValueError(msg)
65 
66 
67 class Color(Either):
68     ''' Accept color values in a variety of ways.
69 
70     For colors, because we support named colors and hex values prefaced
71     with a "#", when we are handed a string value, there is a little
72     interpretation: if the value is one of the 147 SVG named colors or
73     it starts with a "#", then it is interpreted as a value.
74 
75     If a 3-tuple is provided, then it is treated as an RGB (0..255).
76     If a 4-tuple is provided, then it is treated as an RGBa (0..255), with
77     alpha as a float between 0 and 1.  (This follows the HTML5 Canvas API.)
78 
79     Example:
80 
81         .. code-block:: python
82 
83             >>> class ColorModel(HasProps):
84             ...     prop = Color()
85             ...
86 
87             >>> m = ColorModel()
88 
89             >>> m.prop = "firebrick"
90 
91             >>> m.prop = "#a240a2"
92 
93             >>> m.prop = (100, 100, 255)
94 
95             >>> m.prop = (100, 100, 255, 0.5)
96 
97             >>> m.prop = "junk"              # ValueError !!
98 
99             >>> m.prop = (100.2, 57.3, 10.2) # ValueError !!
100 
101     '''
102 
103     def __init__(self, default=None, help=None):
104         types = (Enum(enums.NamedColor),
105                  Regex(r"^#[0-9a-fA-F]{6}$"),
106                  Regex(r"^rgba\(((25[0-5]|2[0-4]\d|1\d{1,2}|\d\d?)\s*,"
107                        r"\s*?){2}(25[0-5]|2[0-4]\d|1\d{1,2}|\d\d?)\s*,"
108                        r"\s*([01]\.?\d*?)\)"),
109                  Regex(r"^rgb\(((25[0-5]|2[0-4]\d|1\d{1,2}|\d\d?)\s*,"
110                        r"\s*?){2}(25[0-5]|2[0-4]\d|1\d{1,2}|\d\d?)\s*?\)"),
111                  Tuple(Byte, Byte, Byte),
112                  Tuple(Byte, Byte, Byte, Percent),
113                  RGB)
114         super(Color, self).__init__(*types, default=default, help=help)
115 
116     def __str__(self):
117         return self.__class__.__name__
118 
119     def transform(self, value):
120         if isinstance(value, tuple):
121             value = colors.RGB(*value).to_css()
122         return value
123 
124     def _sphinx_type(self):
125         return self._sphinx_prop_link()
126 
127 
128 class ColorHex(Color):
129     ''' ref Color
130 
131     The only difference with Color is it's transform in hexadecimal string
132     when send to javascript side
133 
134     '''
135 
136     def transform(self, value):
137         if isinstance(value, string_types):
138             value = value.lower()
139             if value.startswith('rgb'):
140                 value = colors.RGB(*[int(val) for val in re.findall("\d+", value)[:3]]).to_hex()
141             elif value in enums.NamedColor:
142                 value = getattr(colors.named, value).to_hex()
143         elif isinstance(value, tuple):
144             value = colors.RGB(*value).to_hex()
145         else:
146             value = value.to_hex()
147         return value.lower()
148 
149 #-----------------------------------------------------------------------------
150 # Dev API
151 #-----------------------------------------------------------------------------
152 
153 #-----------------------------------------------------------------------------
154 # Private API
155 #-----------------------------------------------------------------------------
156 
157 #-----------------------------------------------------------------------------
158 # Code
159 #-----------------------------------------------------------------------------
160
```
--- 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/bokeh/core/property/color.py b/bokeh/core/property/color.py
--- a/bokeh/core/property/color.py
+++ b/bokeh/core/property/color.py
@@ -137,7 +137,7 @@
         if isinstance(value, string_types):
             value = value.lower()
             if value.startswith('rgb'):
-                value = colors.RGB(*[int(val) for val in re.findall("\d+", value)[:3]]).to_hex()
+                value = colors.RGB(*[int(val) for val in re.findall(r"\d+", value)[:3]]).to_hex()
             elif value in enums.NamedColor:
                 value = getattr(colors.named, value).to_hex()
         elif isinstance(value, tuple):

{"golden_diff": "diff --git a/bokeh/core/property/color.py b/bokeh/core/property/color.py\n--- a/bokeh/core/property/color.py\n+++ b/bokeh/core/property/color.py\n@@ -137,7 +137,7 @@\n         if isinstance(value, string_types):\n             value = value.lower()\n             if value.startswith('rgb'):\n-                value = colors.RGB(*[int(val) for val in re.findall(\"\\d+\", value)[:3]]).to_hex()\n+                value = colors.RGB(*[int(val) for val in re.findall(r\"\\d+\", value)[:3]]).to_hex()\n             elif value in enums.NamedColor:\n                 value = getattr(colors.named, value).to_hex()\n         elif isinstance(value, tuple):\n", "issue": "Color regex needs raw string\nWarning in CI: \r\n\r\n> bokeh/core/property/color.py:137\r\n  /home/travis/build/bokeh/bokeh/bokeh/core/property/color.py:137: DeprecationWarning: invalid escape sequence \\d\r\n    value = colors.RGB(*[int(val) for val in re.findall(\"\\d+\", value)[:3]]).to_hex()\r\n\n", "before_files": [{"content": "#-----------------------------------------------------------------------------\n# Copyright (c) 2012 - 2019, Anaconda, Inc., and Bokeh Contributors.\n# All rights reserved.\n#\n# The full license is in the file LICENSE.txt, distributed with this software.\n#-----------------------------------------------------------------------------\n''' Provide color related properties.\n\n'''\n\n#-----------------------------------------------------------------------------\n# Boilerplate\n#-----------------------------------------------------------------------------\nfrom __future__ import absolute_import, division, print_function, unicode_literals\n\nimport logging\nlog = logging.getLogger(__name__)\n\n#-----------------------------------------------------------------------------\n# Imports\n#-----------------------------------------------------------------------------\n\n# Standard library imports\nimport re\n\n# External imports\nfrom six import string_types\n\n# Bokeh imports\nfrom ... import colors\nfrom .. import enums\nfrom .bases import Property\nfrom .container import Tuple\nfrom .enum import Enum\nfrom .either import Either\nfrom .numeric import Byte, Percent\nfrom .regex import Regex\n\n#-----------------------------------------------------------------------------\n# Globals and constants\n#-----------------------------------------------------------------------------\n\n__all__ = (\n    'Color',\n    'RGB',\n    'ColorHex',\n)\n\n#-----------------------------------------------------------------------------\n# General API\n#-----------------------------------------------------------------------------\n\n\nclass RGB(Property):\n    ''' Accept colors.RGB values.\n\n    '''\n\n    def validate(self, value, detail=True):\n        super(RGB, self).validate(value, detail)\n\n        if not (value is None or isinstance(value, colors.RGB)):\n            msg = \"\" if not detail else \"expected RGB value, got %r\" % (value,)\n            raise ValueError(msg)\n\n\nclass Color(Either):\n    ''' Accept color values in a variety of ways.\n\n    For colors, because we support named colors and hex values prefaced\n    with a \"#\", when we are handed a string value, there is a little\n    interpretation: if the value is one of the 147 SVG named colors or\n    it starts with a \"#\", then it is interpreted as a value.\n\n    If a 3-tuple is provided, then it is treated as an RGB (0..255).\n    If a 4-tuple is provided, then it is treated as an RGBa (0..255), with\n    alpha as a float between 0 and 1.  (This follows the HTML5 Canvas API.)\n\n    Example:\n\n        .. code-block:: python\n\n            >>> class ColorModel(HasProps):\n            ...     prop = Color()\n            ...\n\n            >>> m = ColorModel()\n\n            >>> m.prop = \"firebrick\"\n\n            >>> m.prop = \"#a240a2\"\n\n            >>> m.prop = (100, 100, 255)\n\n            >>> m.prop = (100, 100, 255, 0.5)\n\n            >>> m.prop = \"junk\"              # ValueError !!\n\n            >>> m.prop = (100.2, 57.3, 10.2) # ValueError !!\n\n    '''\n\n    def __init__(self, default=None, help=None):\n        types = (Enum(enums.NamedColor),\n                 Regex(r\"^#[0-9a-fA-F]{6}$\"),\n                 Regex(r\"^rgba\\(((25[0-5]|2[0-4]\\d|1\\d{1,2}|\\d\\d?)\\s*,\"\n                       r\"\\s*?){2}(25[0-5]|2[0-4]\\d|1\\d{1,2}|\\d\\d?)\\s*,\"\n                       r\"\\s*([01]\\.?\\d*?)\\)\"),\n                 Regex(r\"^rgb\\(((25[0-5]|2[0-4]\\d|1\\d{1,2}|\\d\\d?)\\s*,\"\n                       r\"\\s*?){2}(25[0-5]|2[0-4]\\d|1\\d{1,2}|\\d\\d?)\\s*?\\)\"),\n                 Tuple(Byte, Byte, Byte),\n                 Tuple(Byte, Byte, Byte, Percent),\n                 RGB)\n        super(Color, self).__init__(*types, default=default, help=help)\n\n    def __str__(self):\n        return self.__class__.__name__\n\n    def transform(self, value):\n        if isinstance(value, tuple):\n            value = colors.RGB(*value).to_css()\n        return value\n\n    def _sphinx_type(self):\n        return self._sphinx_prop_link()\n\n\nclass ColorHex(Color):\n    ''' ref Color\n\n    The only difference with Color is it's transform in hexadecimal string\n    when send to javascript side\n\n    '''\n\n    def transform(self, value):\n        if isinstance(value, string_types):\n            value = value.lower()\n            if value.startswith('rgb'):\n                value = colors.RGB(*[int(val) for val in re.findall(\"\\d+\", value)[:3]]).to_hex()\n            elif value in enums.NamedColor:\n                value = getattr(colors.named, value).to_hex()\n        elif isinstance(value, tuple):\n            value = colors.RGB(*value).to_hex()\n        else:\n            value = value.to_hex()\n        return value.lower()\n\n#-----------------------------------------------------------------------------\n# Dev API\n#-----------------------------------------------------------------------------\n\n#-----------------------------------------------------------------------------\n# Private API\n#-----------------------------------------------------------------------------\n\n#-----------------------------------------------------------------------------\n# Code\n#-----------------------------------------------------------------------------\n", "path": "bokeh/core/property/color.py"}], "after_files": [{"content": "#-----------------------------------------------------------------------------\n# Copyright (c) 2012 - 2019, Anaconda, Inc., and Bokeh Contributors.\n# All rights reserved.\n#\n# The full license is in the file LICENSE.txt, distributed with this software.\n#-----------------------------------------------------------------------------\n''' Provide color related properties.\n\n'''\n\n#-----------------------------------------------------------------------------\n# Boilerplate\n#-----------------------------------------------------------------------------\nfrom __future__ import absolute_import, division, print_function, unicode_literals\n\nimport logging\nlog = logging.getLogger(__name__)\n\n#-----------------------------------------------------------------------------\n# Imports\n#-----------------------------------------------------------------------------\n\n# Standard library imports\nimport re\n\n# External imports\nfrom six import string_types\n\n# Bokeh imports\nfrom ... import colors\nfrom .. import enums\nfrom .bases import Property\nfrom .container import Tuple\nfrom .enum import Enum\nfrom .either import Either\nfrom .numeric import Byte, Percent\nfrom .regex import Regex\n\n#-----------------------------------------------------------------------------\n# Globals and constants\n#-----------------------------------------------------------------------------\n\n__all__ = (\n    'Color',\n    'RGB',\n    'ColorHex',\n)\n\n#-----------------------------------------------------------------------------\n# General API\n#-----------------------------------------------------------------------------\n\n\nclass RGB(Property):\n    ''' Accept colors.RGB values.\n\n    '''\n\n    def validate(self, value, detail=True):\n        super(RGB, self).validate(value, detail)\n\n        if not (value is None or isinstance(value, colors.RGB)):\n            msg = \"\" if not detail else \"expected RGB value, got %r\" % (value,)\n            raise ValueError(msg)\n\n\nclass Color(Either):\n    ''' Accept color values in a variety of ways.\n\n    For colors, because we support named colors and hex values prefaced\n    with a \"#\", when we are handed a string value, there is a little\n    interpretation: if the value is one of the 147 SVG named colors or\n    it starts with a \"#\", then it is interpreted as a value.\n\n    If a 3-tuple is provided, then it is treated as an RGB (0..255).\n    If a 4-tuple is provided, then it is treated as an RGBa (0..255), with\n    alpha as a float between 0 and 1.  (This follows the HTML5 Canvas API.)\n\n    Example:\n\n        .. code-block:: python\n\n            >>> class ColorModel(HasProps):\n            ...     prop = Color()\n            ...\n\n            >>> m = ColorModel()\n\n            >>> m.prop = \"firebrick\"\n\n            >>> m.prop = \"#a240a2\"\n\n            >>> m.prop = (100, 100, 255)\n\n            >>> m.prop = (100, 100, 255, 0.5)\n\n            >>> m.prop = \"junk\"              # ValueError !!\n\n            >>> m.prop = (100.2, 57.3, 10.2) # ValueError !!\n\n    '''\n\n    def __init__(self, default=None, help=None):\n        types = (Enum(enums.NamedColor),\n                 Regex(r\"^#[0-9a-fA-F]{6}$\"),\n                 Regex(r\"^rgba\\(((25[0-5]|2[0-4]\\d|1\\d{1,2}|\\d\\d?)\\s*,\"\n                       r\"\\s*?){2}(25[0-5]|2[0-4]\\d|1\\d{1,2}|\\d\\d?)\\s*,\"\n                       r\"\\s*([01]\\.?\\d*?)\\)\"),\n                 Regex(r\"^rgb\\(((25[0-5]|2[0-4]\\d|1\\d{1,2}|\\d\\d?)\\s*,\"\n                       r\"\\s*?){2}(25[0-5]|2[0-4]\\d|1\\d{1,2}|\\d\\d?)\\s*?\\)\"),\n                 Tuple(Byte, Byte, Byte),\n                 Tuple(Byte, Byte, Byte, Percent),\n                 RGB)\n        super(Color, self).__init__(*types, default=default, help=help)\n\n    def __str__(self):\n        return self.__class__.__name__\n\n    def transform(self, value):\n        if isinstance(value, tuple):\n            value = colors.RGB(*value).to_css()\n        return value\n\n    def _sphinx_type(self):\n        return self._sphinx_prop_link()\n\n\nclass ColorHex(Color):\n    ''' ref Color\n\n    The only difference with Color is it's transform in hexadecimal string\n    when send to javascript side\n\n    '''\n\n    def transform(self, value):\n        if isinstance(value, string_types):\n            value = value.lower()\n            if value.startswith('rgb'):\n                value = colors.RGB(*[int(val) for val in re.findall(r\"\\d+\", value)[:3]]).to_hex()\n            elif value in enums.NamedColor:\n                value = getattr(colors.named, value).to_hex()\n        elif isinstance(value, tuple):\n            value = colors.RGB(*value).to_hex()\n        else:\n            value = value.to_hex()\n        return value.lower()\n\n#-----------------------------------------------------------------------------\n# Dev API\n#-----------------------------------------------------------------------------\n\n#-----------------------------------------------------------------------------\n# Private API\n#-----------------------------------------------------------------------------\n\n#-----------------------------------------------------------------------------\n# Code\n#-----------------------------------------------------------------------------\n", "path": "bokeh/core/property/color.py"}]}