For the future users' convinience, when you provide lat lon in get_elevation function, it gives the elevation.

    elevation_file = 'Dem.tif'
    def get_elevation(lat, lon):
        coords = ((lat,lon), (lat,lon))
        with rasterio.open(elevation_file) as src:
            vals = src.sample(coords)
            for val in vals:
                elevation=val[0]
                return elevation
    get_elevation(34, 36)