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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 render_build_args(options, ns):
 """Get docker build args dict, rendering any templated args. Args: options (dict):
 The dictionary for a given image from chartpress.yaml. Fields in `options['buildArgs']` will be rendered and returned, if defined. ns (dict):
 the namespace used when rendering templated arguments """

    build_args = options.get('buildArgs', {})
    for key, value in build_args.items():
        build_args[key] = value.format(**ns)
    return build_args