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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 BuildWithPyInstaller(self):
 """Use pyinstaller to build a client package."""

    self.CleanDirectory(
        config.CONFIG.Get("PyInstaller.distpath", context=self.context))

    logging.info("Copying pyinstaller support files")
    self.spec_file = os.path.join(self.build_dir, "grr.spec")

    with open(self.spec_file, "wb") as fd:
      fd.write(config.CONFIG.Get("PyInstaller.spec", context=self.context))

    with open(os.path.join(self.build_dir, "version.txt"), "wb") as fd:
      fd.write(config.CONFIG.Get("PyInstaller.version", context=self.context))

    shutil.copy(
        src=config.CONFIG.Get("PyInstaller.icon_path", context=self.context),
        dst=os.path.join(self.build_dir, u"grr.ico"))

    # We expect the onedir output at this location.
    self.output_dir = os.path.join(
        config.CONFIG.Get("PyInstaller.distpath", context=self.context),
        "grr-client")

    # Pyinstaller doesn't handle unicode strings.
    args = [
        "--distpath",
        str(config.CONFIG.Get("PyInstaller.distpath", context=self.context)),
        "--workpath",
        str(
            config.CONFIG.Get("PyInstaller.workpath_dir",
                              context=self.context)),
        str(self.spec_file)
    ]
    logging.info("Running pyinstaller: %s", args)
    PyInstallerMain.run(pyi_args=[utils.SmartStr(x) for x in args])

    # Clear out some crud that pyinstaller includes.
    for path in ["tcl", "tk", "pytz"]:
      dir_path = os.path.join(self.output_dir, path)
      try:
        shutil.rmtree(dir_path)
      except OSError:
        logging.error("Unable to remove directory: %s", dir_path)

      try:
        os.mkdir(dir_path)
      except OSError:
        logging.error("Unable to create directory: %s", dir_path)

      file_path = os.path.join(dir_path, path)
      try:
        # Create an empty file so the directories get put in the installers.
        with open(file_path, "wb"):
          pass
      except IOError:
        logging.error("Unable to create file: %s", file_path)

    version_ini = version.VersionPath()
    shutil.copy(version_ini, os.path.join(self.output_dir, "version.ini"))

    with open(os.path.join(self.output_dir, "build.yaml"), "wb") as fd:
      self.WriteBuildYaml(fd)