from pyvirtualdisplay import Display
from selenium import webdriver
from selenium.webdriver.common.by import By
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC

display = Display(visible=0, size=(800, 600))
display.start()

browser = webdriver.Firefox()
browser.get('http://www.soda-pro.com/web-services/meteo-data/merra')
browser.find_element_by_id("latId").send_keys('51.5')
browser.find_element_by_id("lonId").send_keys('-0.1')
browser.find_element_by_id("dateBegin").clear()
browser.find_element_by_id("dateBegin").send_keys('2018-01-01')
browser.find_element_by_id("dateEnd").clear()
browser.find_element_by_id("dateEnd").send_keys('2018-12-01')

browser.find_element_by_id("ext-gen70").click()
browser.implicitly_wait(600) # wait seconds

print(browser.find_element_by_link_text("Result file").get_attribute("href"))

browser.quit()

display.stop()