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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 update_input(filelist, ivmlist=None, removed_files=None):
 """ Removes files flagged to be removed from the input filelist. Removes the corresponding ivm files if present. """

    newfilelist = []

    if removed_files == []:
        return filelist, ivmlist
    else:
        sci_ivm = list(zip(filelist, ivmlist))
        for f in removed_files:
            result=[sci_ivm.remove(t) for t in sci_ivm if t[0] == f ]
        ivmlist = [el[1] for el in sci_ivm]
        newfilelist = [el[0] for el in sci_ivm]
        return newfilelist, ivmlist