What is the purpose of a backslash at the end of a line?

问题

Just found the following module import in a Python code:

from sqlalchemy.ext.declarative import declarative_base,\
      AbstractConcreteBase

I am curious about the backslash \ at the end of the first line. What's the purpose of it? Wouldn't it be the same as the following?

from sqlalchemy.ext.declarative import declarative_base, AbstractConcreteBase

回答1:

Yep, it's exactly the same and this is the point of the backslash — it escapes the newline, allowing this long line to be split in two. An alternative is to use parentheses:

from sqlalchemy.ext.declarative import (declarative_base,
      AbstractConcreteBase)

While this is a syntax error:

from sqlalchemy.ext.declarative import declarative_base,
      AbstractConcreteBase

来源：https://stackoverflow.com/questions/16060238/what-is-the-purpose-of-a-backslash-at-the-end-of-a-line