Convert a string to preexisting variable names

How do I convert a string to the variable name in Python?

For example, if the program contains a object named self.post that contains a variable named, I want to do something like:

somefunction("self.post.id") = |Value of self.post.id|

Answer

As referenced in Stack Overflow question Inplace substitution from ConfigParser, you’re looking for eval():

print eval('self.post.id') # Prints the value of self.post.id