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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 checkout_task(current_target):
 """ Update or a local checkout. Arguments target - The target to operate on. """

    try:
        scm = _make_scm(current_target)
        src_dir = current_target.config.get("dp.src_dir")
        shared_dir = current_target.config.get("dp.src_dir_shared")
        scm.checkout(repo_dir=src_dir, shared_dir=shared_dir)
        scm.update(repo_dir=src_dir)
    except devpipeline_core.toolsupport.MissingToolKey as mtk:
        current_target.executor.warning(mtk)