<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def _eval_call(self, node):
 """ Evaluate a function call :param node: Node to eval :return: Result of node """

        try:
            func = self.functions[node.func.id]
        except KeyError:
            raise NameError(node.func.id)

        value = func(
            *(self._eval(a) for a in node.args),
            **dict(self._eval(k) for k in node.keywords)
        )

        if value is True:
            return 1
        elif value is False:
            return 0
        else:
            return value