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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 key_pair_paths(key_name):
 """Returns public and private key paths for a given key_name."""

    public_key_path = os.path.expanduser("~/.ssh/{}.pub".format(key_name))
    private_key_path = os.path.expanduser("~/.ssh/{}.pem".format(key_name))
    return public_key_path, private_key_path