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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 _get_projection(self):
 """Get projection from the NetCDF4 attributes"""

        try:
            proj_str = self.nc.attrs['gdal_projection']
        except TypeError:
            proj_str = self.nc.attrs['gdal_projection'].decode()

        # Check the a/b/h units
        radius_a = proj_str.split('+a=')[-1].split()[0]
        if float(radius_a) > 10e3:
            units = 'm'
            scale = 1.0
        else:
            units = 'km'
            scale = 1e3

        if 'units' not in proj_str:
            proj_str = proj_str + ' +units=' + units

        area_extent = (float(self.nc.attrs['gdal_xgeo_up_left']) / scale,
                       float(self.nc.attrs['gdal_ygeo_low_right']) / scale,
                       float(self.nc.attrs['gdal_xgeo_low_right']) / scale,
                       float(self.nc.attrs['gdal_ygeo_up_left']) / scale)

        return proj_str, area_extent