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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 validate_auth_mechanism_properties(option, value):
 """Validate authMechanismProperties."""

    value = validate_string(option, value)
    props = {}
    for opt in value.split(','):
        try:
            key, val = opt.split(':')
        except ValueError:
            raise ValueError("auth mechanism properties must be "
                             "key:value pairs like SERVICE_NAME:"
                             "mongodb, not %s." % (opt,))
        if key not in _MECHANISM_PROPS:
            raise ValueError("%s is not a supported auth "
                             "mechanism property. Must be one of "
                             "%s." % (key, tuple(_MECHANISM_PROPS)))
        if key == 'CANONICALIZE_HOST_NAME':
            props[key] = validate_boolean_or_string(key, val)
        else:
            props[key] = val

    return props