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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 create_python_bundle(self, dirn, arch):
 """ Create a packaged python bundle in the target directory, by copying all the modules and standard library to the right place. """

        # Todo: find a better way to find the build libs folder
        modules_build_dir = join(
            self.get_build_dir(arch.arch),
            'android-build',
            'build',
            'lib.linux{}-{}-{}'.format(
                '2' if self.version[0] == '2' else '',
                arch.command_prefix.split('-')[0],
                self.major_minor_version_string
            ))

        # Compile to *.pyc/*.pyo the python modules
        self.compile_python_files(modules_build_dir)
        # Compile to *.pyc/*.pyo the standard python library
        self.compile_python_files(join(self.get_build_dir(arch.arch), 'Lib'))
        # Compile to *.pyc/*.pyo the other python packages (site-packages)
        self.compile_python_files(self.ctx.get_python_install_dir())

        # Bundle compiled python modules to a folder
        modules_dir = join(dirn, 'modules')
        c_ext = self.compiled_extension
        ensure_dir(modules_dir)
        module_filens = (glob.glob(join(modules_build_dir, '*.so')) +
                         glob.glob(join(modules_build_dir, '*' + c_ext)))
        info("Copy {} files into the bundle".format(len(module_filens)))
        for filen in module_filens:
            info(" - copy {}".format(filen))
            copy2(filen, modules_dir)

        # zip up the standard library
        stdlib_zip = join(dirn, 'stdlib.zip')
        with current_directory(join(self.get_build_dir(arch.arch), 'Lib')):
            stdlib_filens = list(walk_valid_filens(
                '.', self.stdlib_dir_blacklist, self.stdlib_filen_blacklist))
            info("Zip {} files into the bundle".format(len(stdlib_filens)))
            shprint(sh.zip, stdlib_zip, *stdlib_filens)

        # copy the site-packages into place
        ensure_dir(join(dirn, 'site-packages'))
        ensure_dir(self.ctx.get_python_install_dir())
        # TODO: Improve the API around walking and copying the files
        with current_directory(self.ctx.get_python_install_dir()):
            filens = list(walk_valid_filens(
                '.', self.site_packages_dir_blacklist,
                self.site_packages_filen_blacklist))
            info("Copy {} files into the site-packages".format(len(filens)))
            for filen in filens:
                info(" - copy {}".format(filen))
                ensure_dir(join(dirn, 'site-packages', dirname(filen)))
                copy2(filen, join(dirn, 'site-packages', filen))

        # copy the python .so files into place
        python_build_dir = join(self.get_build_dir(arch.arch),
                                'android-build')
        python_lib_name = 'libpython' + self.major_minor_version_string
        if self.major_minor_version_string[0] == '3':
            python_lib_name += 'm'
        shprint(sh.cp, join(python_build_dir, python_lib_name + '.so'),
                join(self.ctx.dist_dir, self.ctx.dist_name, 'libs', arch.arch))

        info('Renaming .so files to reflect cross-compile')
        self.reduce_object_file_names(join(dirn, 'site-packages'))

        return join(dirn, 'site-packages')