FB2 books rename

#!/usr/bin/env python3
# -*- coding: utf-8 -*-

# источник/назначение
dname_src = 'src'
dname_dst = 'dst'

# формат
fmt = '{0} {1} - {2}.fb2'

# аргументы
args = [
  ['title-info', 'author', 'first-name'],
  ['title-info', 'author', 'last-name'],
  ['title-info', 'book-title'],
]

# режим работы
mode = 'emulation' # только сообщения
#mode = 'copyFile'  # скопировать файлы
#mode = 'moveFile'  # переместить файлы

###

import re
import os
import shutil
from xml.dom import minidom

def getFirst(node, key):
  lst = node.getElementsByTagName(key)
  return lst[0] if lst else None

def getText(node, key, ns):
  node = getFirst(node, key, ns)
  return node.text if node is not None else ''

def solveArg(node, args):
  path = []
  for arg in args:
    path.append(arg)
    node = getFirst(node, arg)
    assert node, "Can't find node '{0}'".format('/'.join(path))
  return node.firstChild.data

def parse(fname, fmt, args):
  root = minidom.parse(fname)
  assert root, "Can't open file '{0}'".format(fname)
  args = [solveArg(root, a) for a in args]
  fname = fmt.format(*args)
  return fname

def makeDirs(dname):
  if os.path.exists(dname) == False:
    os.makedirs(dname)

def modifyFile_emulation(src, dst):
    print('{0} -> {1}'.format(src, dst))

def modifyFile_copyFile(src, dst):
  makeDirs(os.path.dirname(dst))
  shutil.copyfile(src, dst)
  modifyFile_emulation(src, dst)

def modifyFile_moveFile(src, dst):
  makeDirs(os.path.dirname(dst))
  shutil.move(src, dst)
  modifyFile_emulation(src, dst)

modifyFile = {
  "emulation": modifyFile_emulation,
  "copyFile":  modifyFile_copyFile,
  "moveFile":  modifyFile_moveFile,
}[mode]

for dname, dnames, fnames in os.walk(dname_src):
  for fname in fnames:
    if fname[-4:].lower() == '.fb2':
      try:
        fname_src = os.path.join(dname, fname)
        fname_dst = parse(fname_src, fmt, args)
        dst = dname_dst + dname[len(dname_src):]
        dst = os.path.join(dst, fname_dst)
        modifyFile(fname_src, dst)
      except Exception as e:
        print('{0}: {1}'.format(fname_src, e))