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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 init_argparser_build_dir( self, argparser, help=( 'the build directory, where all sources will be copied to ' 'as part of the build process; if left unspecified, the ' 'default behavior is to create a new temporary directory ' 'that will be removed upon conclusion of the build; if ' 'specified, it must be an existing directory and all files ' 'for the build will be copied there instead, overwriting any ' 'existing file, with no cleanup done after.' )):
 """ For setting up build directory """


        argparser.add_argument(
            '--build-dir', default=None, dest=BUILD_DIR,
            metavar=metavar(BUILD_DIR), help=help,
        )