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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 check(self, state, when):
 """ Checks state `state` to see if the breakpoint should fire. :param state: The state. :param when: Whether the check is happening before or after the event. :return: A boolean representing whether the checkpoint should fire. """

        ok = self.enabled and (when == self.when or self.when == BP_BOTH)
        if not ok:
            return ok
        l.debug("... after enabled and when: %s", ok)

        for a in [ _ for _ in self.kwargs if not _.endswith("_unique") ]:
            current_expr = getattr(state.inspect, a)
            needed = self.kwargs.get(a, None)

            l.debug("... checking condition %s", a)

            if current_expr is None and needed is None:
                l.debug("...... both None, True")
                c_ok = True
            elif current_expr is not None and needed is not None:
                if state.solver.solution(current_expr, needed):
                    l.debug("...... is_solution!")
                    c_ok = True
                else:
                    l.debug("...... not solution...")
                    c_ok = False

                if c_ok and self.kwargs.get(a+'_unique', True):
                    l.debug("...... checking uniqueness")
                    if not state.solver.unique(current_expr):
                        l.debug("...... not unique")
                        c_ok = False
            else:
                l.debug("...... one None, False")
                c_ok = False

            ok = ok and c_ok
            if not ok:
                return ok
            l.debug("... after condition %s: %s", a, ok)

        ok = ok and (self.condition is None or self.condition(state))
        l.debug("... after condition func: %s", ok)
        return ok