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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 fields(class_or_instance):
 """Return a tuple describing the fields of this dataclass. Accepts a dataclass or an instance of one. Tuple elements are of type Field. """


    # Might it be worth caching this, per class?
    try:
        fields = getattr(class_or_instance, _FIELDS)
    except AttributeError:
        raise TypeError('must be called with a dataclass type or instance')

    # Exclude pseudo-fields.  Note that fields is sorted by insertion
    # order, so the order of the tuple is as the fields were defined.
    return tuple(f for f in fields.values() if f._field_type is _FIELD)