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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 on_functiondef(self, node):
 """Define procedures."""

        # ('name', 'args', 'body', 'decorator_list')
        if node.decorator_list:
            raise Warning("decorated procedures not supported!")
        kwargs = []

        if not valid_symbol_name(node.name) or node.name in self.readonly_symbols:
            errmsg = "invalid function name (reserved word?) %s" % node.name
            self.raise_exception(node, exc=NameError, msg=errmsg)

        offset = len(node.args.args) - len(node.args.defaults)
        for idef, defnode in enumerate(node.args.defaults):
            defval = self.run(defnode)
            keyval = self.run(node.args.args[idef+offset])
            kwargs.append((keyval, defval))

        if version_info[0] == 3:
            args = [tnode.arg for tnode in node.args.args[:offset]]
        else:
            args = [tnode.id for tnode in node.args.args[:offset]]

        doc = None
        nb0 = node.body[0]
        if isinstance(nb0, ast.Expr) and isinstance(nb0.value, ast.Str):
            doc = nb0.value.s

        varkws = node.args.kwarg
        vararg = node.args.vararg
        if version_info[0] == 3:
            if isinstance(vararg, ast.arg):
                vararg = vararg.arg
            if isinstance(varkws, ast.arg):
                varkws = varkws.arg

        self.symtable[node.name] = Procedure(node.name, self, doc=doc,
                                             lineno=self.lineno,
                                             body=node.body,
                                             args=args, kwargs=kwargs,
                                             vararg=vararg, varkws=varkws)
        if node.name in self.no_deepcopy:
            self.no_deepcopy.remove(node.name)