小编use*_*042的帖子

在Python官方文档说,使用切片运算符和Python中的分配,使切片列表的浅表副本.

但是当我编写代码时,例如:

o = [1, 2, 4, 5]
p = o[:]

当我写:

id(o)
id(p)

我得到不同的id并且还附加一个列表并不反映在另一个列表中.它不是在创建一个深层副本,还是在某个地方我出错了？

我想将 PostgreSQl 与 Django 一起使用。我参考了本教程来安装它，当我运行此命令时

python manage.py syncdb

我收到以下错误

Traceback (most recent call last):
  File "manage.py", line 10, in <module>
    execute_from_command_line(sys.argv)
  File "/usr/local/lib/python2.7/dist-packages/django/core/management/__init__.py", line 453, in execute_from_command_line
    utility.execute()
  File "/usr/local/lib/python2.7/dist-packages/django/core/management/__init__.py", line 392, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/usr/local/lib/python2.7/dist-packages/django/core/management/__init__.py", line 272, in fetch_command
    klass = load_command_class(app_name, subcommand)
  File "/usr/local/lib/python2.7/dist-packages/django/core/management/__init__.py", line 77, in load_command_class
    module = import_module('%s.management.commands.%s' % (app_name, name))
  File "/usr/local/lib/python2.7/dist-packages/django/utils/importlib.py", line 35, in import_module
    __import__(name)
  File "/usr/local/lib/python2.7/dist-packages/django/core/management/commands/syncdb.py", line 8, in <module>
    from django.core.management.sql import custom_sql_for_model, emit_post_sync_signal
  File "/usr/local/lib/python2.7/dist-packages/django/core/management/sql.py", line …