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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 valid_totp( token, secret, digest_method=hashlib.sha1, token_length=6, interval_length=30, clock=None, window=0, ):
 """Check if given token is valid time-based one-time password for given secret. :param token: token which is being checked :type token: int or str :param secret: secret for which the token is being checked :type secret: str :param digest_method: method of generating digest (hashlib.sha1 by default) :type digest_method: callable :param token_length: length of the token (6 by default) :type token_length: int :param interval_length: length of TOTP interval (30 seconds by default) :type interval_length: int :param clock: time in epoch seconds to generate totp for, default is now :type clock: int :param window: compensate for clock skew, number of intervals to check on each side of the current time. (default is 0 - only check the current clock time) :type window: int (positive) :return: True, if is valid token, False otherwise :rtype: bool True False True False """

    if _is_possible_token(token, token_length=token_length):
        if clock is None:
            clock = time.time()
        for w in range(-window, window+1):
            if int(token) == get_totp(
                secret,
                digest_method=digest_method,
                token_length=token_length,
                interval_length=interval_length,
                clock=int(clock)+(w*interval_length)
            ):
                return True
    return False