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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 password_hash(password, password_salt=None):
 """Hashes a specified password"""

    password_salt = password_salt or oz.settings["session_salt"]
    salted_password = password_salt + password
    return "sha256!%s" % hashlib.sha256(salted_password.encode("utf-8")).hexdigest()