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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 parse_secured_key(secured_key, key_nonce_separator='.', nonce_length=4, base=BASE62):
 """ Parse a given secured key and return its associated integer, the key itself, and the embedded nonce. @param secured_key a string representation of a secured key composed of a key in Base62, a separator character, and a nonce. @param key_nonce_separator: the character that is used to separate the key and the nonce to form the secured key. @param nonce_length: the number of characters to compose the nonce. @param base: a sequence of characters that is used to encode the integer value. @return: a tuple ``(value, key, nonce)``: * ``value``: the integer value of the key. * ``key``: the plain-text key. * ``nonce``: "number used once", a pseudo-random number to ensure that the key cannot be reused in replay attacks. @raise ValueError: if the format of the secured key is invalid, or if the embedded nonce is of the wrong length. """

    parts = secured_key.split(key_nonce_separator)
    if len(parts) != 2:
        raise ValueError('Invalid secured key format')

    (key, nonce) = parts
    if len(nonce) != nonce_length:
        raise ValueError('Invalid length of the key nonce')

    return key_to_int(key, base=base), key, nonce