什么是在“[笔记本]”“PIP安装IPython的[笔记本]”是什么意思？

Question

的“[笔记本]”似乎是某种改性剂，但不是IPython的我突然在想，因为我是在安装Jupyter什么此修改器我已经错过了，或许一些会安装特定的其他变种内核或配置。

不幸的是，我不知道'[notebook]'是什么：pip search '[notebook]'找不到任何东西，我不知道这个修饰符是什么或被调用。我已经看过PyPI命名约定pep等，但是我找不到任何引用'[']'符号的东西。

我没有看到任何标识的安装后，可以帮助我确定我已经安装了这个特殊的修改？

osmith:~ oliver.smith$ pip3 install ipython[notebook] 
Requirement already satisfied: ipython[notebook] in /usr/local/lib/python3.6/site-packages 
Requirement already satisfied: prompt-toolkit<2.0.0,>=1.0.4 in /usr/local/lib/python3.6/site-packages (from ipython[notebook]) 
Requirement already satisfied: setuptools>=18.5 in /usr/local/lib/python3.6/site-packages (from ipython[notebook]) 
Requirement already satisfied: pexpect; sys_platform != "win32" in /usr/local/lib/python3.6/site-packages (from ipython[notebook]) 
Requirement already satisfied: decorator in /usr/local/lib/python3.6/site-packages (from ipython[notebook]) 
Requirement already satisfied: jedi>=0.10 in /usr/local/lib/python3.6/site-packages (from ipython[notebook]) 
Requirement already satisfied: traitlets>=4.2 in /usr/local/lib/python3.6/site-packages (from ipython[notebook]) 
Requirement already satisfied: appnope; sys_platform == "darwin" in /usr/local/lib/python3.6/site-packages (from ipython[notebook]) 
Requirement already satisfied: pygments in /usr/local/lib/python3.6/site-packages (from ipython[notebook]) 
Requirement already satisfied: pickleshare in /usr/local/lib/python3.6/site-packages (from ipython[notebook]) 
Requirement already satisfied: simplegeneric>0.8 in /usr/local/lib/python3.6/site-packages (from ipython[notebook]) 
Requirement already satisfied: ipywidgets; extra == "notebook" in /usr/local/lib/python3.6/site-packages (from ipython[notebook]) 
Requirement already satisfied: notebook; extra == "notebook" in /usr/local/lib/python3.6/site-packages (from ipython[notebook]) 
Requirement already satisfied: wcwidth in /usr/local/lib/python3.6/site-packages (from prompt-toolkit<2.0.0,>=1.0.4->ipython[notebook]) 
Requirement already satisfied: six>=1.9.0 in /usr/local/lib/python3.6/site-packages (from prompt-toolkit<2.0.0,>=1.0.4->ipython[notebook]) 
Requirement already satisfied: ptyprocess>=0.5 in /usr/local/lib/python3.6/site-packages (from pexpect; sys_platform != "win32"->ipython[notebook]) 
Requirement already satisfied: ipython-genutils in /usr/local/lib/python3.6/site-packages (from traitlets>=4.2->ipython[notebook]) 
Requirement already satisfied: widgetsnbextension~=2.0.0 in /usr/local/lib/python3.6/site-packages (from ipywidgets; extra == "notebook"->ipython[notebook]) 
Requirement already satisfied: ipykernel>=4.5.1 in /usr/local/lib/python3.6/site-packages (from ipywidgets; extra == "notebook"->ipython[notebook]) 
Requirement already satisfied: nbformat>=4.2.0 in /usr/local/lib/python3.6/site-packages (from ipywidgets; extra == "notebook"->ipython[notebook]) 
Requirement already satisfied: terminado>=0.3.3; sys_platform != "win32" in /usr/local/lib/python3.6/site-packages (from notebook; extra == "notebook"->ipython[notebook]) 
Requirement already satisfied: jupyter-client in /usr/local/lib/python3.6/site-packages (from notebook; extra == "notebook"->ipython[notebook]) 
Requirement already satisfied: tornado>=4 in /usr/local/lib/python3.6/site-packages (from notebook; extra == "notebook"->ipython[notebook]) 
Requirement already satisfied: jinja2 in /usr/local/lib/python3.6/site-packages (from notebook; extra == "notebook"->ipython[notebook]) 
Requirement already satisfied: jupyter-core in /usr/local/lib/python3.6/site-packages (from notebook; extra == "notebook"->ipython[notebook]) 
Requirement already satisfied: nbconvert in /usr/local/lib/python3.6/site-packages (from notebook; extra == "notebook"->ipython[notebook]) 
Requirement already satisfied: jsonschema!=2.5.0,>=2.4 in /usr/local/lib/python3.6/site-packages (from nbformat>=4.2.0->ipywidgets; extra == "notebook"->ipython[notebook]) 
Requirement already satisfied: python-dateutil>=2.1 in /usr/local/lib/python3.6/site-packages (from jupyter-client->notebook; extra == "notebook"->ipython[notebook]) 
Requirement already satisfied: pyzmq>=13 in /usr/local/lib/python3.6/site-packages (from jupyter-client->notebook; extra == "notebook"->ipython[notebook]) 
Requirement already satisfied: MarkupSafe>=0.23 in /usr/local/lib/python3.6/site-packages (from jinja2->notebook; extra == "notebook"->ipython[notebook]) 
Requirement already satisfied: mistune!=0.6 in /usr/local/lib/python3.6/site-packages (from nbconvert->notebook; extra == "notebook"->ipython[notebook]) 
Requirement already satisfied: entrypoints>=0.2.2 in /usr/local/lib/python3.6/site-packages (from nbconvert->notebook; extra == "notebook"->ipython[notebook]) 
Requirement already satisfied: bleach in /usr/local/lib/python3.6/site-packages (from nbconvert->notebook; extra == "notebook"->ipython[notebook]) 
Requirement already satisfied: pandocfilters>=1.4.1 in /usr/local/lib/python3.6/site-packages (from nbconvert->notebook; extra == "notebook"->ipython[notebook]) 
Requirement already satisfied: testpath in /usr/local/lib/python3.6/site-packages (from nbconvert->notebook; extra == "notebook"->ipython[notebook]) 
Requirement already satisfied: html5lib>=0.99999999 in /usr/local/lib/python3.6/site-packages (from bleach->nbconvert->notebook; extra == "notebook"->ipython[notebook]) 
Requirement already satisfied: webencodings in /usr/local/lib/python3.6/site-packages (from html5lib>=0.99999999->bleach->nbconvert->notebook; extra == "notebook"->ipython[notebook]) 
osmith:~ oliver.smith$ pip3 show ipython 
Name: ipython 
Version: 6.1.0 
Summary: IPython: Productive Interactive Computing 
Home-page: https://ipython.org 
Author: The IPython Development Team 
Author-email: ipython-dev@python.org 
License: BSD 
Location: /usr/local/lib/python3.6/site-packages 
Requires: jedi, prompt-toolkit, pygments, traitlets, pexpect, simplegeneric, pickleshare, setuptools, appnope, decorator 
osmith:~ oliver.smith$ pip3 show ipython[notebook] 
osmith:~ oliver.smith$ 

Answer 1

方括号表示正常情况下不安装临时演员。

此链接解释说，在细节： https://setuptools.readthedocs.io/en/latest/setuptools.html#declaring-dependencies

此链接详细解释了要求符，并列出了方括号作为一个选项： https://pip.pypa.io/en/stable/reference/pip_install/#requirement-specifiers