prompt: You will be provided with a partial code base and an issue statement explaining a problem to resolve.
  <issue>
  Add python 3.8 support
  #### What's the problem this feature will solve?
  <!-- What are you trying to do, that you are unable to achieve with pip-tools as it currently stands? -->
  
  Python 3.8 is released, so it's time to support it. 
  
  #### Describe the solution you'd like
  <!-- A clear and concise description of what you want to happen. -->
  
  1. add "py37" env to `tox.ini`
  1. remove 3.8-dev from `.travis.yml`
  1. add "Programming Language :: Python :: 3.8" classifier to `setup.py`
  1. add "3.8" dimension to `.travis.yml` (supported, see https://travis-ci.community/t/add-python-3-8-support/5463)
  1. add "py37" dimension to `.appveyor.yml` (not supported yet, but will be on the nex image update, tracking issue: https://github.com/appveyor/ci/issues/3142)
  1. add "3.8" to python-version list in `.github/workflows/cron.yml` (not supported yet, tracking issue: https://github.com/actions/setup-python/issues/30)
  
  <!-- Provide examples of real-world use cases that this would enable and how it solves the problem described above. -->
  
  #### Alternative Solutions
  <!-- Have you tried to workaround the problem using pip-tools or other tools? Or a different approach to solving this issue? Please elaborate here. -->
  
  N/A
  
  #### Additional context
  <!-- Add any other context, links, etc. about the feature here. -->
  
  https://discuss.python.org/t/python-3-8-0-is-now-available/2478
  
  </issue>
  <code>
  [start of setup.py]
  1 """
  2 pip-tools keeps your pinned dependencies fresh.
  3 """
  4 from os.path import abspath, dirname, join
  5 
  6 from setuptools import find_packages, setup
  7 
  8 
  9 def read_file(filename):
  10     """Read the contents of a file located relative to setup.py"""
  11     with open(join(abspath(dirname(__file__)), filename)) as thefile:
  12         return thefile.read()
  13 
  14 
  15 setup(
  16     name="pip-tools",
  17     use_scm_version=True,
  18     url="https://github.com/jazzband/pip-tools/",
  19     license="BSD",
  20     author="Vincent Driessen",
  21     author_email="me@nvie.com",
  22     description=__doc__.strip(),
  23     long_description=read_file("README.rst"),
  24     long_description_content_type="text/x-rst",
  25     packages=find_packages(exclude=["tests"]),
  26     package_data={},
  27     python_requires=">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*",
  28     setup_requires=["setuptools_scm"],
  29     install_requires=["click>=6", "six"],
  30     zip_safe=False,
  31     entry_points={
  32         "console_scripts": [
  33             "pip-compile = piptools.scripts.compile:cli",
  34             "pip-sync = piptools.scripts.sync:cli",
  35         ]
  36     },
  37     platforms="any",
  38     classifiers=[
  39         "Development Status :: 5 - Production/Stable",
  40         "Intended Audience :: Developers",
  41         "Intended Audience :: System Administrators",
  42         "License :: OSI Approved :: BSD License",
  43         "Operating System :: OS Independent",
  44         "Programming Language :: Python",
  45         "Programming Language :: Python :: 2",
  46         "Programming Language :: Python :: 2.7",
  47         "Programming Language :: Python :: 3",
  48         "Programming Language :: Python :: 3.5",
  49         "Programming Language :: Python :: 3.6",
  50         "Programming Language :: Python :: 3.7",
  51         "Programming Language :: Python :: Implementation :: CPython",
  52         "Programming Language :: Python :: Implementation :: PyPy",
  53         "Topic :: System :: Systems Administration",
  54     ],
  55 )
  56
  [end of setup.py]
  </code>
  
  I need you to solve this issue by generating a single patch file that I can apply directly to this repository using git apply. Please respond with a single patch file in the following format.
  <patch>
  diff --git a/file.py b/file.py
  --- a/file.py
  +++ b/file.py
  @@ -1,27 +1,35 @@
   def euclidean(a, b):
  -    while b:
  -        a, b = b, a % b
  -    return a
  +    if b == 0:
  +        return a
  +    return euclidean(b, a % b)
   
   
   def bresenham(x0, y0, x1, y1):
       points = []
       dx = abs(x1 - x0)
       dy = abs(y1 - y0)
  -    sx = 1 if x0 < x1 else -1
  -    sy = 1 if y0 < y1 else -1
  -    err = dx - dy
  +    x, y = x0, y0
  +    sx = -1 if x0 > x1 else 1
  +    sy = -1 if y0 > y1 else 1
   
  -    while True:
  -        points.append((x0, y0))
  -        if x0 == x1 and y0 == y1:
  -            break
  -        e2 = 2 * err
  -        if e2 > -dy:
  -            err -= dy
  -            x0 += sx
  -        if e2 < dx:
  -            err += dx
  -            y0 += sy
  +    if dx > dy:
  +        err = dx / 2.0
  +        while x != x1:
  +            points.append((x, y))
  +            err -= dy
  +            if err < 0:
  +                y += sy
  +                err += dx
  +            x += sx
  +    else:
  +        err = dy / 2.0
  +        while y != y1:
  +            points.append((x, y))
  +            err -= dx
  +            if err < 0:
  +                x += sx
  +                err += dy
  +            y += sy
  +
  +    points.append((x, y))
       return points
  
  </patch>
golden_diff: diff --git a/setup.py b/setup.py
  --- a/setup.py
  +++ b/setup.py
  @@ -48,6 +48,7 @@
           "Programming Language :: Python :: 3.5",
           "Programming Language :: Python :: 3.6",
           "Programming Language :: Python :: 3.7",
  +        "Programming Language :: Python :: 3.8",
           "Programming Language :: Python :: Implementation :: CPython",
           "Programming Language :: Python :: Implementation :: PyPy",
           "Topic :: System :: Systems Administration",
  
verification_info: {"golden_diff": "diff --git a/setup.py b/setup.py\n--- a/setup.py\n+++ b/setup.py\n@@ -48,6 +48,7 @@\n         \"Programming Language :: Python :: 3.5\",\n         \"Programming Language :: Python :: 3.6\",\n         \"Programming Language :: Python :: 3.7\",\n+        \"Programming Language :: Python :: 3.8\",\n         \"Programming Language :: Python :: Implementation :: CPython\",\n         \"Programming Language :: Python :: Implementation :: PyPy\",\n         \"Topic :: System :: Systems Administration\",\n", "issue": "Add python 3.8 support\n#### What's the problem this feature will solve?\r\n<!-- What are you trying to do, that you are unable to achieve with pip-tools as it currently stands? -->\r\n\r\nPython 3.8 is released, so it's time to support it. \r\n\r\n#### Describe the solution you'd like\r\n<!-- A clear and concise description of what you want to happen. -->\r\n\r\n1. add \"py37\" env to `tox.ini`\r\n1. remove 3.8-dev from `.travis.yml`\r\n1. add \"Programming Language :: Python :: 3.8\" classifier to `setup.py`\r\n1. add \"3.8\" dimension to `.travis.yml` (supported, see https://travis-ci.community/t/add-python-3-8-support/5463)\r\n1. add \"py37\" dimension to `.appveyor.yml` (not supported yet, but will be on the nex image update, tracking issue: https://github.com/appveyor/ci/issues/3142)\r\n1. add \"3.8\" to python-version list in `.github/workflows/cron.yml` (not supported yet, tracking issue: https://github.com/actions/setup-python/issues/30)\r\n\r\n<!-- Provide examples of real-world use cases that this would enable and how it solves the problem described above. -->\r\n\r\n#### Alternative Solutions\r\n<!-- Have you tried to workaround the problem using pip-tools or other tools? Or a different approach to solving this issue? Please elaborate here. -->\r\n\r\nN/A\r\n\r\n#### Additional context\r\n<!-- Add any other context, links, etc. about the feature here. -->\r\n\r\nhttps://discuss.python.org/t/python-3-8-0-is-now-available/2478\n", "before_files": [{"content": "\"\"\"\npip-tools keeps your pinned dependencies fresh.\n\"\"\"\nfrom os.path import abspath, dirname, join\n\nfrom setuptools import find_packages, setup\n\n\ndef read_file(filename):\n    \"\"\"Read the contents of a file located relative to setup.py\"\"\"\n    with open(join(abspath(dirname(__file__)), filename)) as thefile:\n        return thefile.read()\n\n\nsetup(\n    name=\"pip-tools\",\n    use_scm_version=True,\n    url=\"https://github.com/jazzband/pip-tools/\",\n    license=\"BSD\",\n    author=\"Vincent Driessen\",\n    author_email=\"me@nvie.com\",\n    description=__doc__.strip(),\n    long_description=read_file(\"README.rst\"),\n    long_description_content_type=\"text/x-rst\",\n    packages=find_packages(exclude=[\"tests\"]),\n    package_data={},\n    python_requires=\">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*\",\n    setup_requires=[\"setuptools_scm\"],\n    install_requires=[\"click>=6\", \"six\"],\n    zip_safe=False,\n    entry_points={\n        \"console_scripts\": [\n            \"pip-compile = piptools.scripts.compile:cli\",\n            \"pip-sync = piptools.scripts.sync:cli\",\n        ]\n    },\n    platforms=\"any\",\n    classifiers=[\n        \"Development Status :: 5 - Production/Stable\",\n        \"Intended Audience :: Developers\",\n        \"Intended Audience :: System Administrators\",\n        \"License :: OSI Approved :: BSD License\",\n        \"Operating System :: OS Independent\",\n        \"Programming Language :: Python\",\n        \"Programming Language :: Python :: 2\",\n        \"Programming Language :: Python :: 2.7\",\n        \"Programming Language :: Python :: 3\",\n        \"Programming Language :: Python :: 3.5\",\n        \"Programming Language :: Python :: 3.6\",\n        \"Programming Language :: Python :: 3.7\",\n        \"Programming Language :: Python :: Implementation :: CPython\",\n        \"Programming Language :: Python :: Implementation :: PyPy\",\n        \"Topic :: System :: Systems Administration\",\n    ],\n)\n", "path": "setup.py"}]}