Dynamic programming to find the optimal path

dynamic.py, find the optimal path based on dynamic programming

import matplotlib.pyplot as plt
import pylab as pl
import connmysql
import pandas as pd

sql2 = "SELECT id, distance,duration FROM  trafic"
checklist = connmysql.getdata(sql2)
ids=[]
for i in range(0,len(checklist)):
    ids.append(checklist[i][0])
time_dataframe = pd.DataFrame(columns=['distance','duration'], index=ids)
# print(time_dataframe)
for i in range(0,len(checklist)):
    id=checklist[i][0]
    time_dataframe.at[ids[i],'distance'] = float(checklist[i][1])#distance
    time_dataframe.at[ids[i], 'duration'] = float(checklist[i][2] ) # distance
# id='100001-100002'
# print(time_dataframe.at[id,'distance'])
# print(time_dataframe.at['100001-100002','duration'])
# list=['100002','100003','100004','100005','100006']
        #Based on dynamic programming to find the shortest path, the amount of calculation will be relatively small and the speed will be faster
list = ['100002', '100003', '100004', '100005', '100006']
# Based on dynamic programming to find the shortest path, the amount of calculation will be relatively small and the speed will be faster
routelist=[]
route_distance=[]
for j in range(0,len(list)-1):
    print('mm',j)
    print('he1', routelist)
    print('he2', route_distance)
    ids = []
    distances, routes = {}, {}
    for i in range(0, len(list)):
        if len(routelist)==0:#When there is no target in it
            id = list[0] + '-'+list[i]
            if list[i]!=list[0]:
                ids.append(id)
        else:
            if list[i] not in routelist :#The calculated points are no longer recalculated
                id =  routelist[j]+ '-'+list[i]
                ids.append(id)
    print('he3',ids)
    for k in range(0, len(ids)):
        distances[ids[k]] = time_dataframe.at[ids[k], 'distance']
    print('he4',distances)
    route1 = sorted(distances.items(), key=lambda item: item[1]) # Take out the minimum distance
    route_distance.append(route1[0])
    # routes[route1[0][0]] = route1[0][1] # key:100002-100006,values: 3929.0,, save the optimal route from the last point
    print('he5',route1)
    a=route1[0][0].split('-')
    if a[0] not in routelist:
        routelist.append(a[0])
    if a[1] not in routelist:
        routelist.append(a[1])
    print('he6', routelist)
print('he',routelist)