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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 get_hiera_key(key_name):
 """Retrieve a key from the hiera store :param password_name: Name of the key to retrieve :type password_name: type """

    command = ["hiera", key_name]
    p = subprocess.Popen(command, stdout=subprocess.PIPE)
    out, err = p.communicate()
    return out