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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 df64bitto32bit(tbl):
 """ Convert a Pandas dataframe from 64 bit types to 32 bit types to save memory or disk space. Parameters tbl : The dataframe to convert Returns ------- The converted dataframe """

    newtbl = pd.DataFrame(index=tbl.index)
    for colname in tbl.columns:
        newtbl[colname] = series64bitto32bit(tbl[colname])
    return newtbl