Method of realizing distance and azimuth between two latitude and longitude points by python

Recently do something about GPS trajectory, spend more mind, two commonly used functions summed up under 1, seeking distance and seeking azimuth, more accurate, welcome to exchange!

1. Find the azimuth angle of two latitude and longitude points, P0 (latA, lonA), P1 (latB, lonB) (many blogs are not very good, so summarize it here)

def getDegree(latA, lonA, latB, lonB):
  """
  Args:
    point p1(latA, lonA)
    point p2(latB, lonB)
  Returns:
    bearing between the two GPS points,
    default: the basis of heading direction is north
  """
  radLatA = radians(latA)
  radLonA = radians(lonA)
  radLatB = radians(latB)
  radLonB = radians(lonB)
  dLon = radLonB - radLonA
  y = sin(dLon) * cos(radLatB)
  x = cos(radLatA) * sin(radLatB) - sin(radLatA) * cos(radLatB) * cos(dLon)
  brng = degrees(atan2(y, x))
  brng = (brng + 360) % 360
  return brng

2. Find the distance function between two latitude and longitude points: P0 (latA, lonA), P1 (latB, lonB)

def getDistance(latA, lonA, latB, lonB):
  ra = 6378140 # radius of equator: meter
  rb = 6356755 # radius of polar: meter
  flatten = (ra - rb) / ra # Partial rate of the earth
  # change angle to radians
  radLatA = radians(latA)
  radLonA = radians(lonA)
  radLatB = radians(latB)
  radLonB = radians(lonB)
 
  pA = atan(rb / ra * tan(radLatA))
  pB = atan(rb / ra * tan(radLatB))
  x = acos(sin(pA) * sin(pB) + cos(pA) * cos(pB) * cos(radLonA - radLonB))
  c1 = (sin(x) - x) * (sin(pA) + sin(pB))**2 / cos(x / 2)**2
  c2 = (sin(x) + x) * (sin(pA) - sin(pB))**2 / sin(x / 2)**2
  dr = flatten / 8 * (c1 - c2)
  distance = ra * (x + dr)
  return distance