Importing v reloading modules modules

[Terry Reedy]

Reload is effectively deprecated in 2.x and removed in 3.x, so I 
recommend not using it.

Deleting an entry from sys.modules should force recreation with an 
import. Just make sure all other references are also gone so that the 
module object can be deleted.

The following shows how to import by name in string and globally from 
within a function.

def f():
     global itertools
     itertools = __import__('itertools')

f()
print(itertools) # 3.1

#<module 'itertools' (built-in)>

Terry Jan Reedy