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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 from_lt(rsize, ltm, ltv):
 """Compute the corner location and pixel size in units of unbinned pixels. .. note:: Translated from ``calacs/lib/fromlt.c``. Parameters rsize : int Reference pixel size. Usually 1. ltm, ltv : tuple of float See :func:`get_lt`. Returns ------- bin : tuple of int Pixel size in X and Y. corner : tuple of int Corner of subarray in X and Y. """

    dbinx = rsize / ltm[0]
    dbiny = rsize / ltm[1]

    dxcorner = (dbinx - rsize) - dbinx * ltv[0]
    dycorner = (dbiny - rsize) - dbiny * ltv[1]

    # Round off to the nearest integer.
    bin = (_nint(dbinx), _nint(dbiny))
    corner = (_nint(dxcorner), _nint(dycorner))

    return bin, corner