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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 read_frame(qs, fieldnames=(), index_col=None, coerce_float=False, verbose=True, datetime_index=False):
 """ Returns a dataframe from a QuerySet Optionally specify the field names/columns to utilize and a field as the index Parameters qs: The Django QuerySet. fieldnames: The model field names to use in creating the frame. You can span a relationship in the usual Django way by using double underscores to specify a related field in another model You can span a relationship in the usual Django way by using double underscores to specify a related field in another model index_col: specify the field to use for the index. If the index field is not in the field list it will be appended coerce_float : boolean, default False Attempt to convert values to non-string, non-numeric data (like decimal.Decimal) to floating point, useful for SQL result sets verbose: boolean If this is ``True`` then populate the DataFrame with the human readable versions of any foreign key fields else use the primary keys values. The human readable version of the foreign key field is defined in the ``__unicode__`` or ``__str__`` methods of the related class definition datetime_index: specify whether index should be converted to a DateTimeIndex. """


    if fieldnames:
        fieldnames = pd.unique(fieldnames)
        if index_col is not None and index_col not in fieldnames:
            # Add it to the field names if not already there
            fieldnames = tuple(fieldnames) + (index_col,)
        fields = to_fields(qs, fieldnames)
    elif is_values_queryset(qs):
        if django.VERSION < (1, 9):  # pragma: no cover
            annotation_field_names = list(qs.query.annotation_select)

            if annotation_field_names is None:
                annotation_field_names = []

            extra_field_names = qs.extra_names
            if extra_field_names is None:
                extra_field_names = []

            select_field_names = qs.field_names

        else:  # pragma: no cover
            annotation_field_names = list(qs.query.annotation_select)
            extra_field_names = list(qs.query.extra_select)
            select_field_names = list(qs.query.values_select)

        fieldnames = select_field_names + annotation_field_names + \
            extra_field_names
        fields = [None if '__' in f else qs.model._meta.get_field(f)
                  for f in select_field_names] + \
            [None] * (len(annotation_field_names) + len(extra_field_names))

        uniq_fields = set()
        fieldnames, fields = zip(
            *(f for f in zip(fieldnames, fields)
              if f[0] not in uniq_fields and not uniq_fields.add(f[0])))
    else:
        fields = qs.model._meta.fields
        fieldnames = [f.name for f in fields]
        fieldnames += list(qs.query.annotation_select.keys())

    if is_values_queryset(qs):
        recs = list(qs)
    else:
        recs = list(qs.values_list(*fieldnames))

    df = pd.DataFrame.from_records(recs, columns=fieldnames,
                                   coerce_float=coerce_float)

    if verbose:
        update_with_verbose(df, fieldnames, fields)

    if index_col is not None:
        df.set_index(index_col, inplace=True)

    if datetime_index:
        df.index = pd.to_datetime(df.index, errors="ignore")
    return df