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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 exit_proc(self, lineno):
 """ Exits current procedure. Local labels are transferred to global scope unless they have been marked as local ones. Raises an error if no current local context (stack underflow) """

        __DEBUG__('Exiting current scope from lineno %i' % lineno)

        if len(self.local_labels) <= 1:
            error(lineno, 'ENDP in global scope (with no PROC)')
            return

        for label in self.local_labels[-1].values():
            if label.local:
                if not label.defined:
                    error(lineno, "Undefined LOCAL label '%s'" % label.name)
                    return
                continue

            name = label.name
            _lineno = label.lineno
            value = label.value

            if name not in self.global_labels.keys():
                self.global_labels[name] = label
            else:
                self.global_labels[name].define(value, _lineno)

        self.local_labels.pop()  # Removes current context
        self.scopes.pop()