利用Python如何实现根据URL地址下载并保存文件至对应目录

import os


def get_file(root_path, all_files={}):
  '''
  递归函数，遍历该文档目录和子目录下的所有文件，获取其path
  '''
  files = os.listdir(root_path)
  for file in files:
    if not os.path.isdir(root_path + '/' + file):  # not a dir
      all_files[file] = root_path + '/' + file
    else: # is a dir
      get_file((root_path+'/'+file), all_files)
  return all_files


if __name__ == '__main__':
  path = './raw_data'
  print(get_file(path))

for filename, path in paths.items():
    print('reading file: {}'.format(filename))
    with open(path, 'r') as f:
      lines = f.readlines()
      url_list = []
      for line in lines:
        url_list.append(line.strip('\n'))
      print(url_list)

foldername = "./picture_get_by_url/pic_download/{}".format(filename.split('.')[0])
if not os.path.exists(folder_path):
    print("Selected folder not exist, try to create it.")
    os.makedirs(folder_path)

def get_pic_by_url(folder_path, lists):
  if not os.path.exists(folder_path):
    print("Selected folder not exist, try to create it.")
    os.makedirs(folder_path)
  for url in lists:
    print("Try downloading file: {}".format(url))
    filename = url.split('/')[-1]
    filepath = folder_path + '/' + filename
    if os.path.exists(filepath):
      print("File have already exist. skip")
    else:
      try:
        urllib.request.urlretrieve(url, filename=filepath)
      except Exception as e:
        print("Error occurred when downloading file, error message:")
        print(e)

import os


def get_file(root_path, all_files={}):
  '''
  递归函数，遍历该文档目录和子目录下的所有文件，获取其path
  '''
  files = os.listdir(root_path)
  for file in files:
    if not os.path.isdir(root_path + '/' + file):  # not a dir
      all_files[file] = root_path + '/' + file
    else: # is a dir
      get_file((root_path+'/'+file), all_files)
  return all_files


if __name__ == '__main__':
  path = './raw_data'
  print(get_file(path))

import get_doc_path
import os
import urllib.request


def get_pic_by_url(folder_path, lists):
  if not os.path.exists(folder_path):
    print("Selected folder not exist, try to create it.")
    os.makedirs(folder_path)
  for url in lists:
    print("Try downloading file: {}".format(url))
    filename = url.split('/')[-1]
    filepath = folder_path + '/' + filename
    if os.path.exists(filepath):
      print("File have already exist. skip")
    else:
      try:
        urllib.request.urlretrieve(url, filename=filepath)
      except Exception as e:
        print("Error occurred when downloading file, error message:")
        print(e)


if __name__ == "__main__":
  root_path = './picture_get_by_url/raw_data'
  paths = get_doc_path.get_file(root_path)
  print(paths)
  for filename, path in paths.items():
    print('reading file: {}'.format(filename))
    with open(path, 'r') as f:
      lines = f.readlines()
      url_list = []
      for line in lines:
        url_list.append(line.strip('\n'))
      foldername = "./picture_get_by_url/pic_download/{}".format(filename.split('.')[0])
      get_pic_by_url(foldername, url_list)