You can use type to create a new class on the fly and then instantiate it. Like so:

>>> t = type('test', (object,), {})()
>>> t
<__main__.test at 0xb615930c>

The arguments to type are: Class name, a tuple of base classes, and the object's dictionary. Which can contain functions (the object's methods) or attributes.

You can actually shorten the first line to

>>> t = type('test', (), {})()
>>> t.__class__.__bases__
(object,)

Because by default type creates new style classes that inherit from object.

type is used in Python for metaprogramming.

But if you just want to create an instance of object. Then, just create an instance of it. Like lejlot suggests.

Creating an instance of a new class like this has an important difference that may be useful.

>>> a = object()
>>> a.whoops = 1
Traceback (most recent call last):
   File "<stdin>", line 1, in <module>
AttributeError: 'object' object has no attribute 'whoops'

Where as:

>>> b = type('', (), {})()
>>> b.this_works = 'cool'
>>> 

bpy.ops.object.empty_add()

You can call bpy.ops.object.empty_add() operator per object and pass the location, rotation and scale for each object as well:

Blender 2.8+

import bpy

for obj in bpy.context.selected_objects:
    # Create the empty using the operator
    bpy.ops.object.empty_add(type='PLAIN_AXES', location=obj.location)
    # Get the newly created empty
    empty = bpy.context.view_layer.objects.active
    # Set the size
    empty.empty_display_size = 20
    # Parent the object to the empty
    obj.parent = empty

Blender 2.7x

import bpy

selected_objs = bpy.context.selected_objects
for obj in selected_objs:
    # Create the empty using the operator
    bpy.ops.object.empty_add(type='PLAIN_AXES', location=obj.location)
    # Get the newly created empty
    empty = bpy.context.scene.objects.active
    # Parent the object to the empty
    obj.parent = empty

I think it's quite straightforward, tell me if you have problems

I made a function based on the answer by TLousky (Tested in Blender 3.2)

# Makes an empty, at location, stores it in existing collection
def make_empty(name, location, coll_name): #string, vector, string of existing coll
    empty_obj = bpy.data.objects.new( "empty", None, )
    empty_obj.name = name
    empty_obj.empty_display_size = 1 
    bpy.data.collections[coll_name].objects.link(empty_obj)
    empty_obj.location = location
    return empty_obj

I dont get your point but you may use namedtuple :

>>>from collections import namedtuple

>>>foo = namedtuple('foo', "data tuple dict")
>>>foo.data = ""
''
>>> foo.tuple = ()
>>> foo.tuple
()