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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 __get_wbfmt_usrfld(self, data_nt):
 """Return format for text cell from namedtuple field specified by 'ntfld_wbfmt'"""

        if self.ntfld_wbfmt is not None:
            if isinstance(self.ntfld_wbfmt, str):
                ntval = getattr(data_nt, self.ntfld_wbfmt, None) # Ex: 'section'
                if ntval is not None:
                    return self.fmtname2wbfmtobj.get(ntval, None)