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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 _init_fields(self):
 """Creates the `_fields`, `_forms` asn `_sets` dicts. Any properties which begin with an underscore or are not `Field`, `Form` or `FormSet` **instances** are ignored by this method. """

        fields = {}
        forms = {}
        sets = {}

        for name in dir(self):
            if name.startswith('_'):
                continue
            field = getattr(self, name)
            is_field = isinstance(field, Field)
            is_form = isinstance(field, Form) or (
                inspect.isclass(field) and issubclass(field, Form))
            is_set = isinstance(field, FormSet)

            if is_field:
                field = copy(field)
                field.name = self._prefix + name
                field.form = self
                if field.prepare is None:
                    field.prepare = getattr(self, 'prepare_' + name, None)
                if field.clean is None:
                    field.clean = getattr(self, 'clean_' + name, None)
                fields[name] = field
                setattr(self, name, field)
            elif is_form:
                forms[name] = field
            elif is_set:
                field._name = self._prefix + name  # REALLY IMPORTANT
                sets[name] = field

        self._fields = fields
        self._forms = forms
        self._sets = sets