How to append a modified list into a list?

[jfong at ms4.hinet.net]

I have a working list 'tbl' and recording list 'm'. I want to append 'tbl' into 'm' each time when the 'tbl' was modified. I will record the change by append it through the function 'apl'.

For example:

>>>tbl=[0,0]
>>>m=[]

>>>tbl[0]=1
>>>apl(tbl)
>>>m
[[1,0]]

>>>tbl[1]=2
>>>apl(tbl)
>>>m
[[1,0], [1,2]]

How to define this function properly?

Obviously the most intuitive way doesn't work.
def apl0(tbl):
    m.append(tbl)

and introducing a local variable will not help either.
def apl1(tbl):
    w=tbl
    m.append(w)

I figure out a workable way, but looks ugly.
def apl2(tbl):
    w=[]
    w[:]=tbl
    m.append(w)

I know those binding tricks between names and objects. Just wondering if there is an elegant way of doing this:-)

--Jach