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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 getGeometry(self,ra=None,dec=None):
 """Return an array of rectangles that represent the 'ra,dec' corners of the FOV"""


        import math,ephem
        ccds=[]

        if ra is None:
            ra=self.ra
        if dec is None:
            dec=self.dec
        self.ra=ephem.hours(ra)
        self.dec=ephem.degrees(dec)
        for geo in self.geometry[self.camera]:
            ycen=math.radians(geo["dec"])+dec
            xcen=math.radians(geo["ra"])/math.cos(ycen)+ra
            dy=math.radians(geo["ddec"])
            dx=math.radians(geo["dra"]/math.cos(ycen))
            ccds.append([xcen-dx/2.0,ycen-dy/2.0,xcen+dx/2.0,ycen+dy/2.0])

        return ccds