I happened upon this post by Nick Rodgers: https://medium.com/@nicholasRodgers/sidestepping-pythons-reload-function-without-restarting-maya-2448bab9476eIt deletes the previous imports so they’ll get imported freshly every time. Just posting it here in case I’ll need it again and can’t find the post anymore.

import inspect
from os.path import dirname
import sys
 
 
# I'm going to define this little function to make this cleaner
# It's going to have a flag to let you specify the userPath you want to clear out
# But otherwise I'd going to assume that it's the userPath you're running the script from (__file__)
def resetSessionForScript(userPath=None):
    if userPath is None:
        userPath = dirname(__file__)
    # Convert this to lower just for a clean comparison later
    userPath = userPath.lower()
 
    print userPath
 
    toDelete = []
    # Iterate over all the modules that are currently loaded
    for key, module in sys.modules.iteritems():
        # There's a few modules that are going to complain if you try to query them
        # so I've popped this into a try/except to keep it safe
        try:
            # Use the "inspect" library to get the moduleFilePath that the current module was loaded from
            moduleFilePath = inspect.getfile(module).lower()
 
            # Don't try and remove the startup script, that will break everything
            if moduleFilePath == __file__.lower():
                continue
 
            # If the module's filepath contains the userPath, add it to the list of modules to delete
            if moduleFilePath.startswith(userPath):
                print "Removing %s" % key
                toDelete.append(key)
        except:
            pass
 
    # If we'd deleted the module in the loop above, it would have changed the size of the dictionary and
    # broken the loop. So now we go over the list we made and delete all the modules
    for module in toDelete:
        del (sys.modules[module])