Module loader, to replace (somewhat) python's import. Does not work on .pyc - it's mainly for user files.

moduleloader.py

import os, sys, new

modules = { }

def loadModule(moduleName, locals_dict={}):
    """ 
    Imports a module without using the built-in import functions.
    
    Parameters:
    moduleName - The name of the module, same as if you were using __import__ or import
    locals_dict - The dictionary of locals to use when loading the module.
    globals_dict - The dictionary of globals to use when loading the module.
    
    Returns the loaded module environment, similar to __import__ (but without using sys.modules, thus allowing re-loading)
    """
    moduleFile = __find_file(moduleName)
    fh = open(moduleFile, "rU")
    exec fh in locals_dict
    fh.close()
    
    mod = new.module(moduleName)
    setattr(mod, "__file__", moduleFile)
    setattr(mod, "__name__", moduleName)
    if moduleFile.endswith("__init__.py"):
        setattr(mod, "__package__", moduleFile[:-12])
    else:
        setattr(mod, "__package__", None)
        
    for k,v in locals_dict.items():
        setattr(mod, k, v)
        
    modules[moduleName] = mod
    return mod

def __find_file(moduleName): #throws ImportError
    moduleName = moduleName.replace(".", os.sep)
    for path in sys.path:
        if not path.endswith(".zip"):
            if path == "":
                if os.path.isfile(moduleName+".py"):
                    # if the module's location is in a package, call loadModule again to load the package first
                    if os.path.isfile(os.path.join(os.getcwd(), "__init__.py")):
                        loadModule(path)
                        
                    return moduleName+".py"
                elif os.path.isdir(moduleName):
                    if os.path.isfile(os.path.join(moduleName, "__init__.py")):
                        return os.path.join(moduleName, "__init__.py")
                    else:
                        raise ImportError("Invalid package. (missing __init__.py)")
            else:
                if os.path.isfile(os.path.join(path, moduleName+".py")):
                    # if the module's location is in a package, call loadModule again to load the package first
                    if os.path.isfile(os.path.join(path, "__init__.py")):
                        loadModule(path)
                        
                    return os.path.join(path, moduleName+".py")
                elif os.path.isdir(os.path.join(path, moduleName)):
                    if os.path.isfile(os.path.join(path, moduleName, "__init__.py")):
                        return os.path.join(path, moduleName, "__init__.py")
                    else:
                        raise ImportError("Invalid package. (missing __init__.py)")
    
    #if we got here, we couldn't find the module or package
    raise ImportError("No such module.")