PyCharm中设置默认的签名：

#!/usr/bin/env python
# -*- coding=utf-8 -*-
__author__ = 'TT'
__CreateAt__ = '2017/8/28-下午2:30'

设置方式
File and Code Templates

File | Settings | Editor | File and Code Templates for Windows and Linux 
PyCharm | Preferences | Editor | File and Code Templates for macOS 
#### 
File->Default Settings->Editor->File and Code Templete -> Python Script

键入内容

#!/usr/bin/env python
# -*- coding=utf-8 -*-
__author__= 'TT'
__CreateAt__='${DATE}-${TIME}'

参考jetbrain官网http://www.jetbrains.com/help/pycharm/file-and-code-templates-2.html

directive or will be defined during the file creation.
Variables to be expanded into corresponding values in the
${<variable_name>} format.The available predefined file template variables are:
${PROJECT_NAME}

• the name of the current project.
  ${NAME}
• the name of the new file which you specify in the New Filedialog box during the file creation.
  ${USER}
• the login name of the current user.
  ${DATE}
• the current system date.
  ${TIME}
• the current system time.
  ${YEAR}
• the current year.
  ${MONTH}
• the current month.
  ${DAY}
• the current day of the month.
  ${HOUR}
• the current hour.
  ${MINUTE}
• the current minute.
  ${PRODUCT_NAME}
• the name of the IDE in which the file will be created.
  ${MONTH_NAME_SHORT}
• the first 3 letters of the month name. Example: Jan, Feb, etc.
  ${MONTH_NAME_FULL}
• full name of a month. Example: January, February, etc.

Treating dollar sign
You can prevent treating dollar characters ($
) in template variables as prefixes. If you need a dollar character ($
inserted as is, use the ${DS}
file template variable instead. When the template is applied, this variable evaluates to a plain dollar character ($
).Examples:
To use some version control keywords (such as $Revision$
, $Date$
, etc.) in your default class template, write ${DS}
instead of the dollar prefix ($
).
The template code ${DS}this
will be rendered as $this
.