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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 convert(self, converters, in_place=False):
 """ Applies transformations to the dataset. :param converters: A dictionary specifying the function to apply to each field. If a field is missing from the dictionary, then it will not be transformed. :param in_place: Whether to perform the transformation in place or create a new dataset instance :return: the transformed dataset instance """

        dataset = self if in_place else self.__class__(OrderedDict([(name, data[:]) for name, data in self.fields.items()]))
        for name, convert in converters.items():
            if name not in self.fields.keys():
                raise InvalidFieldsException('Converter specified for non-existent field {}'.format(name))
            for i, d in enumerate(dataset.fields[name]):
                dataset.fields[name][i] = convert(d)
        return dataset