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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 build_hstwcs(crval1, crval2, crpix1, crpix2, naxis1, naxis2, pscale, orientat):
 """ Create an `stwcs.wcsutil.HSTWCS` object for a default instrument without distortion based on user provided parameter values. """

    wcsout = wcsutil.HSTWCS()
    wcsout.wcs.crval = np.array([crval1, crval2])
    wcsout.wcs.crpix = np.array([crpix1, crpix2])
    wcsout.naxis1 = naxis1
    wcsout.naxis2 = naxis2
    wcsout.wcs.cd = buildRotMatrix(orientat) * [-1, 1] * pscale / 3600.0
    # Synchronize updates with astropy.wcs objects
    wcsout.wcs.set()
    wcsout.setPscale()
    wcsout.setOrient()
    wcsout.wcs.ctype = ['RA---TAN', 'DEC--TAN']

    return wcsout