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The Parse library provides many built-in functions. Furthermore, each application can define its own functions. Every function is associated with a function ID number. Built-in functions have ID numbers assigned to them in the library code; application-defined functions are given ID numbers by the application. ID numbers are word-sized unsigned integers. All built-in (&quot;internal&quot;) functions have ID numbers which are less than the constant FUNCTION_ID_FIRST_EXTERNAL_FUNCTION_BASE; all appli