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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 _check_parameter_range(s_min, s_max):
 r"""Performs a final check on a clipped parameter range. .. note:: This is a helper for :func:`clip_range`. If both values are unchanged from the "unset" default, this returns the whole interval :math:`\left[0.0, 1.0\right]`. If only one of the values is set to some parameter :math:`s`, this returns the "degenerate" interval :math:`\left[s, s\right]`. (We rely on the fact that ``s_min`` must be the only set value, based on how :func:`_update_parameters` works.) Otherwise, this simply returns ``[s_min, s_max]``. Args: s_min (float):
 Current start of clipped interval. If "unset", this value will be ``DEFAULT_S_MIN``. s_max (float):
 Current end of clipped interval. If "unset", this value will be ``DEFAULT_S_MAX``. Returns: Tuple[float, float]: The (possibly updated) start and end of the clipped parameter range. """

    if s_min == DEFAULT_S_MIN:
        # Based on the way ``_update_parameters`` works, we know
        # both parameters must be unset if ``s_min``.
        return 0.0, 1.0

    if s_max == DEFAULT_S_MAX:
        return s_min, s_min

    return s_min, s_max