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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 _copytree(src, dst):
 """Similar to shutils.copytree, except that dst is already there """

    try:
        os.makedirs(dst)
    except OSError:
        pass  # It must already exist
    for file in os.listdir(src):
        try:
            shutil.copy2('%s/%s' % (src, file), '%s/%s' % (dst, file))
        except IOError, e:
            try:
                shutil.copytree('%s/%s' % (src, file), '%s/%s' % (dst, file))
            except OSError:  # Not a directory, reraise copy2 exception
                raise e