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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 handle_input(self, input_hdr):
 """ This method tries to ensure that the input data has the correct dimensions. INPUTS: input_hdr (no default) Header from which data shape is to be extracted. """


        input_slice = input_hdr['NAXIS']*[0]

        for i in range(input_hdr['NAXIS']):
            if input_hdr['CTYPE%d'%(i+1)].startswith("RA"):
                input_slice[-1] = slice(None)
            if input_hdr['CTYPE%d'%(i+1)].startswith("DEC"):
                input_slice[-2] = slice(None)

        return input_slice