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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 dump_str(self, names=None, child_lists=None, verbose=False):
 """Dump fields as a string. For debugging. :param names: the list of fields to include or None for all public fields :param child_lists: dictionary of child command names to fields for that child command to include :param verbose: if True, prefix each line with the command class and display fields as a dictionary; if False, dump just the field values with tabs between them """

        interesting = {}
        if names is None:
            fields = [
                k for k in list(self.__dict__.keys())
                if not k.startswith(b'_')
            ]
        else:
            fields = names
        for field in fields:
            value = self.__dict__.get(field)
            if field in self._binary and value is not None:
                value = b'(...)'
            interesting[field] = value
        if verbose:
            return "%s: %s" % (self.__class__.__name__, interesting)
        else:
            return "\t".join([repr(interesting[k]) for k in fields])