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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 set_bp(cls, ctx, register, address, trigger, watch):
 """ Sets a hardware breakpoint. @see: clear_bp, find_slot @type ctx: dict( str S{->} int ) @param ctx: Thread context dictionary. @type register: int @param register: Slot (debug register). @type address: int @param address: Memory address. @type trigger: int @param trigger: Trigger flag. See L{HardwareBreakpoint.validTriggers}. @type watch: int @param watch: Watch flag. See L{HardwareBreakpoint.validWatchSizes}. """

        Dr7 = ctx['Dr7']
        Dr7 |= cls.enableMask[register]
        orMask, andMask = cls.triggerMask[register][trigger]
        Dr7 &= andMask
        Dr7 |= orMask
        orMask, andMask = cls.watchMask[register][watch]
        Dr7 &= andMask
        Dr7 |= orMask
        ctx['Dr7'] = Dr7
        ctx['Dr%d' % register] = address