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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 create_pointing(self,event):
 """Plot the sky coverage of pointing at event.x,event.y on the canavas"""


        import math
        (ra,dec)=self.c2p((self.canvasx(event.x),
                           self.canvasy(event.y)))
        this_camera=camera(camera=self.camera.get())
        ccds=this_camera.getGeometry(ra,dec)
        items=[]
        for ccd in ccds:
            (x1,y1)=self.p2c((ccd[0],ccd[1]))
            (x2,y2)=self.p2c((ccd[2],ccd[3]))
            item=self.create_rectangle(x1,y1,x2,y2)
            items.append(item)
	label={}
	label['text']=w.plabel.get()
	label['id']=self.label(this_camera.ra,this_camera.dec,label['text'])
        self.pointings.append({
		"label": label,
		"items": items,
		"camera": this_camera} )
        self.current_pointing(len(self.pointings)-1)