Question: how to calculate distance between two coordinates in python?
Answer: R = 6373.0. radius of the Earth.
lat1 = math. radians(52.2296756) ... 
lon1 = math. radians(21.0122287)
lat2 = math. radians(52.406374)
lon2 = math. radians(16.9251681)
dlon = lon2 - lon1. change in coordinates.
dlat = lat2 - lat1.
a = math.