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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 cmp_val_salt_hash(val, salt, str_hash):
 """ Given a string, salt, & hash validate the string The salt & val will be concatented as in gen_salt_and hash() & compared to the provided hash. This will only ever work with hashes derived from gen_salt_and_hash() :param val: clear-text string :param salt: string salt :param str_hash: existing hash to compare against :return: boolean """


    computed_hash = hashlib.sha256(val + salt).hexdigest()
    return computed_hash == str_hash