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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 rc_params(usetex=None):
 """Returns a new `matplotlib.RcParams` with updated GWpy parameters The updated parameters are globally stored as `gwpy.plot.rc.GWPY_RCPARAMS`, with the updated TeX parameters as `gwpy.plot.rc.GWPY_TEX_RCPARAMS`. .. note:: This function doesn't apply the new `RcParams` in any way, just creates something that can be used to set `matplotlib.rcParams`. Parameters usetex : `bool`, `None` value to set for `text.usetex`; if `None` determine automatically using the ``GWPY_USETEX`` environment variable, and whether `tex` is available on the system. If `True` is given (or determined) a number of other parameters are updated to improve TeX formatting. Examples -------- """

    # if user didn't specify to use tex or not, guess based on
    # the `GWPY_USETEX` environment variable, or whether tex is
    # installed at all.
    if usetex is None:
        usetex = bool_env(
            'GWPY_USETEX',
            default=rcParams['text.usetex'] or tex.has_tex())

    # build RcParams from matplotlib.rcParams with GWpy extras
    rcp = GWPY_RCPARAMS.copy()
    if usetex:
        rcp.update(GWPY_TEX_RCPARAMS)
    return rcp