old_contents: import shutil
  import os
  import re
  
  from setuptools import setup, find_packages
  from setuptools.command.install import install
  from setuptools.command.develop import develop
  
  
  PROJECT_ROOT = os.path.dirname(os.path.realpath(__file__))
  REQUIREMENTS_FILE = os.path.join(PROJECT_ROOT, 'requirements.txt')
  
  with open(REQUIREMENTS_FILE) as buff:
      install_reqs = buff.read().splitlines()
  
  
  def copy_styles():
      from matplotlib import get_configdir
      sd = os.path.join(get_configdir(), "stylelib")
      source = os.path.dirname(os.path.realpath(__file__))
      lsd = os.path.join(source, 'arviz', 'plots', 'styles')
      styles = [f for f in os.listdir(lsd)]
      if not os.path.isdir(sd):
          os.makedirs(sd)
      for s in styles:
          shutil.copy(os.path.join(lsd, s), os.path.join(sd, s))
  
  class DevelopStyles(develop):
      def run(self):
          copy_styles()
          develop.run(self)
  
  class InstallStyles(install):
      def run(self):
          copy_styles()
          install.run(self)
  
  def get_version():
      VERSIONFILE = join('arviz', '__init__.py')
      lines = open(VERSIONFILE, 'rt').readlines()
      version_regex = r"^__version__ = ['\"]([^'\"]*)['\"]"
      for line in lines:
          mo = re.search(version_regex, line, re.M)
          if mo:
              return mo.group(1)
      raise RuntimeError('Unable to find version in %s.' % (VERSIONFILE,))
  
  setup(
      name='arviz',
      version=get_version(),
      description='Exploratory analysis of Bayesian models',
      author='ArviZ Developers',
      url="http://github.com/arviz-devs/arviz",
      packages=find_packages(),
      install_requires=install_reqs,
      include_package_data=True,
      cmdclass={
          'develop': DevelopStyles,
          'install': InstallStyles,
      },
  )
  
new_contents: import shutil
  import os
  import re
  
  from setuptools import setup, find_packages
  from setuptools.command.install import install
  from setuptools.command.develop import develop
  
  
  PROJECT_ROOT = os.path.dirname(os.path.realpath(__file__))
  REQUIREMENTS_FILE = os.path.join(PROJECT_ROOT, 'requirements.txt')
  
  with open(REQUIREMENTS_FILE) as buff:
      install_reqs = buff.read().splitlines()
  
  
  def copy_styles():
      from matplotlib import get_configdir
      sd = os.path.join(get_configdir(), "stylelib")
      source = os.path.dirname(os.path.realpath(__file__))
      lsd = os.path.join(source, 'arviz', 'plots', 'styles')
      styles = [f for f in os.listdir(lsd)]
      if not os.path.isdir(sd):
          os.makedirs(sd)
      for s in styles:
          shutil.copy(os.path.join(lsd, s), os.path.join(sd, s))
  
  class DevelopStyles(develop):
      def run(self):
          copy_styles()
          develop.run(self)
  
  class InstallStyles(install):
      def run(self):
          copy_styles()
          install.run(self)
  
  def get_version():
      VERSIONFILE = os.path.join('arviz', '__init__.py')
      lines = open(VERSIONFILE, 'rt').readlines()
      version_regex = r"^__version__ = ['\"]([^'\"]*)['\"]"
      for line in lines:
          mo = re.search(version_regex, line, re.M)
          if mo:
              return mo.group(1)
      raise RuntimeError('Unable to find version in %s.' % (VERSIONFILE,))
  
  setup(
      name='arviz',
      version=get_version(),
      description='Exploratory analysis of Bayesian models',
      author='ArviZ Developers',
      url="http://github.com/arviz-devs/arviz",
      packages=find_packages(),
      install_requires=install_reqs,
      include_package_data=True,
      cmdclass={
          'develop': DevelopStyles,
          'install': InstallStyles,
      },
  )
  
subject: use os.path.join