Use of Substitute () in Python template

In Python, the template can be used to fix the formatting of strings and reuse them.

The template belongs to a class in string and can be invoked in the following ways to use his words:

 from string Import Template

We use the following code:

>>> s = Template ('there  ${moneytype} is  ${money}')' Dollar ', money=)

Run results show "there Dollar is 12"

So we can replace the data in it.

But we're going to replace one of those data?

>>> print S.substitute (Moneytype ='Dollar') Traceback (most recent): File"<pyshell#509>", line1,inch<module>Print S.substitute (Moneytype='Dollar') File"C:\Python27\lib\string.py", line172,inchSubstitutereturnself.pattern.sub (Convert, self.template) File"C:\Python27\lib\string.py", line162,inchconvert Val=Mapping[named]keyerror:' Money'

An error has been made. It doesn't look like this.

This is going to use the safe_substitute.

' Dollar ' ) There  is  ${money}

Note: I previously looked at the reference book $ after using the "()" bracket, but I ran an error on the 2.7.9, and then tried it, bold later version does not support "()". There is no problem using "{}" or not writing parentheses.

Use of Substitute () in Python template