Creating a function object from a string

The following puts the symbols that you define in your string in the dictionary d:

d = {}
exec "def f(x): return x" in d

Now d['f'] is a function object. If you want to use variables from your program in the code in your string, you can send this via d:

d = {'a':7}
exec "def f(x): return x + a" in d

Now d['f'] is a function object that is dynamically bound to d['a']. When you change d['a'], you change the output of d['f']().

can't you do something like this?

>>> def func_builder(name):
...  def f():
...   # multiline code here, using name, and using the logic you have
...   return name
...  return f
... 
>>> func_builder("ciao")()
'ciao'

basically, assemble a real function instead of assembling a string and then trying to compile that into a function.