How to assign a module to a variable even if it's not defined?

[mandaxyz]

New question: "How to create a module or variable with the name from a string?"

import sys
import os
import importlib

dir = os.path.dirname(bpy.data.filepath)
dir = os.path.join(dir, "Scripts") # The script must be located in that folder
if not dir in sys.path:
    sys.path.append(dir)
'''
#---------- Method 1 ----------
# There is no problem if there is no 'for', but I will have many modules, so I can't do these.
main = importlib.import_module('main')
MyModule = importlib.import_module('MyModule')'''

#---------- Method 2 ----------
module_names = (
    'main',
    'MyModule')

for name in module_names:
    value = importlib.import_module(name)
    create_var_by_str(name, value) # FIXME: Here is my problem, I want to create a variable named of the
                                   # value of 'name', and assign to it the value of 'value'.