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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def pkg_resources_env(self, platform_str):
 """Returns a dict that can be used in place of packaging.default_environment."""

    os_name = ''
    platform_machine = ''
    platform_release = ''
    platform_system = ''
    platform_version = ''
    sys_platform = ''

    if 'win' in platform_str:
      os_name = 'nt'
      platform_machine = 'AMD64' if '64' in platform_str else 'x86'
      platform_system = 'Windows'
      sys_platform = 'win32'
    elif 'linux' in platform_str:
      os_name = 'posix'
      platform_machine = 'x86_64' if '64' in platform_str else 'i686'
      platform_system = 'Linux'
      sys_platform = 'linux2' if self._version[0] == 2 else 'linux'
    elif 'macosx' in platform_str:
      os_name = 'posix'
      platform_str = platform_str.replace('.', '_')
      platform_machine = platform_str.split('_', 3)[-1]
      # Darwin version are macOS version + 4
      platform_release = '{}.0.0'.format(int(platform_str.split('_')[2]) + 4)
      platform_system = 'Darwin'
      platform_version = 'Darwin Kernel Version {}'.format(platform_release)
      sys_platform = 'darwin'

    return {
      'implementation_name': self.interpreter.lower(),
      'implementation_version': self.version_str,
      'os_name': os_name,
      'platform_machine': platform_machine,
      'platform_release': platform_release,
      'platform_system': platform_system,
      'platform_version': platform_version,
      'python_full_version': self.version_str,
      'platform_python_implementation': self.interpreter,
      'python_version': self.version_str[:3],
      'sys_platform': sys_platform,
    }