It is a string formatting syntax (which it borrows from C).
Please see “PyFormat”:
Python supports formatting values into
strings. Although this can include
very complicated expressions, the most
basic usage is to insert values into a
string with the%s
placeholder.
Here is a really simple example:
#Python 2
name = raw_input("who are you? ")
print "hello %s" % (name,)
#Python 3+
name = input("who are you? ")
print("hello %s" % (name,))
The %s
token allows me to insert (and potentially format) a string. Notice that the %s
token is replaced by whatever I pass to the string after the %
symbol. Notice also that I am using a tuple here as well (when you only have one string using a tuple is optional) to illustrate that multiple strings can be inserted and formatted in one statement.