docs: def MatchBuildContext(self,
                          target_os,
                          target_arch,
                          target_package,
                          context=None):
      """Return true if target_platforms matches the supplied parameters.
  
      Used by buildanddeploy to determine what clients need to be built.
  
      Args:
        target_os: which os we are building for in this run (linux, windows,
          darwin)
        target_arch: which arch we are building for in this run (i386, amd64)
        target_package: which package type we are building (exe, dmg, deb, rpm)
        context: config_lib context
  
      Returns:
        bool: True if target_platforms spec matches parameters.
      """
      for spec in self.Get("ClientBuilder.target_platforms", context=context):
        spec_os, arch, package_name = spec.split("_")
        if (spec_os == target_os and arch == target_arch and
            package_name == target_package):
          return True
      return False