old_contents: from math import radians, cos, sin, asin, sqrt
  
  AVG_EARTH_RADIUS = 6371  # in km
  
  
  def haversine(point1, point2, miles=False):
      """ Calculate the great-circle distance between two points on the Earth surface.
  
      :input: two 2-tuples, containing the latitude and longitude of each point
      in decimal degrees.
  
      Example: haversine((45.7597, 4.8422), (48.8567, 2.3508))
  
      :output: Returns the distance bewteen the two points.
      The default unit is kilometers. Miles can be returned
      if the ``miles`` parameter is set to True.
  
      """
      # unpack latitude/longitude
      lat1, lng1 = point1
      lat2, lng2 = point2
  
      # convert all latitudes/longitudes from decimal degrees to radians
      lat1, lng1, lat2, lng2 = map(radians, (lat1, lng1, lat2, lng2))
  
      # calculate haversine
      lat = lat2 - lat1
      lng = lng2 - lng1
      d = sin(lat * 0.5) ** 2 + cos(lat1) * cos(lat2) * sin(lng * 0.5) ** 2
      h = 2 * AVG_EARTH_RADIUS * asin(sqrt(d))
      if miles:
          return h * 0.621371  # in miles
      else:
          return h  # in kilometers
  
  
new_contents: from math import radians, cos, sin, asin, sqrt
  
  AVG_EARTH_RADIUS = 6371  # in km
  MILES_PER_KILOMETER = 0.621371
  
  def haversine(point1, point2, miles=False):
      """ Calculate the great-circle distance between two points on the Earth surface.
  
      :input: two 2-tuples, containing the latitude and longitude of each point
      in decimal degrees.
  
      Example: haversine((45.7597, 4.8422), (48.8567, 2.3508))
  
      :output: Returns the distance between the two points.
      The default unit is kilometers. Miles can be returned
      if the ``miles`` parameter is set to True.
  
      """
      # unpack latitude/longitude
      lat1, lng1 = point1
      lat2, lng2 = point2
  
      # convert all latitudes/longitudes from decimal degrees to radians
      lat1, lng1, lat2, lng2 = map(radians, (lat1, lng1, lat2, lng2))
  
      # calculate haversine
      lat = lat2 - lat1
      lng = lng2 - lng1
      d = sin(lat * 0.5) ** 2 + cos(lat1) * cos(lat2) * sin(lng * 0.5) ** 2
      h = 2 * AVG_EARTH_RADIUS * asin(sqrt(d))
      if miles:
          return h * MILES_PER_KILOMETER # in miles
      else:
          return h  # in kilometers
  
  
subject: Update __init__.py