import os

import itertools

import matplotlib.pyplot as plt

import pandas as pd

import pvlib

from pvlib import clearsky, atmosphere, solarposition

from pvlib.location import Location

from pvlib.iotools import read_tmy3

tus = Location(34.6937378, 135.5021651, 'Asia/Tokyo', 100, 'Tokyo')

times = pd.DatetimeIndex(start='2019-07-01', end='2019-07-04', freq='1min', tz=tus.tz)

cs = tus.get_clearsky(times)

cs.plot()

plt.show()