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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 strip_pad(hdu):
 """Remove the padding lines that CFHT adds to headers"""

    
    l = hdu.header.ascardlist()
    d = []
    for index in range(len(l)):
        if l[index].key in __comment_keys and str(l[index])==__cfht_padding:
            d.append(index)
    d.reverse()
    for index in d:
        del l[index]
    return(0)