Python：os.walk到特定的目录和文件

Question

I have a file structure that looks like:

|num_1

|----|dir1

|--------|dir2

|------------|dcm

|----------------\file_1

|----------------\file_2

|----------------\file_n

|num_2

|----|dir1

|--------|dcm

|------------\file_1

|------------\file_n

|num_n

I want to us os.walk (or something more appropriate?) to traverse the tree until it finds the directory "dcm". dcm can be at varying levels of the tree

This is what I have. Thanks!

import dicom
import re
import os

dcm = []
PATH = "C:\foo"

#find the directory we want to get to, save path
for path, dirs in os.walk(PATH): 
    for dirname in dirs:
        fullpath = os.path.join(path,dirname)
        if "dcm" in dirname:
            #copied this first_file line - just want a fast and easy way to grab ONE file in the dcm directory
            #without reading any of the others (for time reasons)
            first_file = next((join(path, f) for f in os.listdir(path) if isfile(join(path, f))),"none")
            fullpath = os.path.join(fullpath,first_file)
            dcm.append(fullpath)

Answer 1

I went ahead with the "lazy" way and used listdir to read out all of the files under the dcm directory - decided that the resource cost wasn't too high. That being said, I think that pulling out a single random file from a directory without reading all of those files is an interesting query that someone more Python oriented than I should answer!

For reference, my final solution was... do excuse the inefficiencies in iterator usage! I am new and needed a quick solution

for path, dirs, filename in os.walk(rootDir): #omit files, loop through later
    for dirname in dirs:
        fullpath = os.path.join(path,dirname)
        if "dcm" in dirname:
            dcm.append(fullpath)

final = []
uni = 0
final.append(dcm[0])
for i in range(len(dcm)):
    if len(os.listdir(dcm[i])) < 10:
        pass
    elif dcm[i][16:19] != final[uni][16:19]:
        final.append(dcm[i])
        uni += 1


tags = ((0x8, 0x70)),((0x8, 0x1090)), ((0x18, 0x1020))
values = []
printout = []
for p in range(len(final)):
    file = os.path.join(final[p],os.listdir(final[p])[0])
    ds = dicom.read_file(file)
    printout.append([final[p]])
    for k in range(len(tags)):
        printout.append([ds[tags[k]]])