Lazy Import for Diffusers (#4829)
* initial commit
* move modules to import struct
* add dummy objects and _LazyModule
* add lazy import to schedulers
* clean up unused imports
* lazy import on models module
* lazy import for schedulers module
* add lazy import to pipelines module
* lazy import altdiffusion
* lazy import audio diffusion
* lazy import audioldm
* lazy import consistency model
* lazy import controlnet
* lazy import dance diffusion ddim ddpm
* lazy import deepfloyd
* lazy import kandinksy
* lazy imports
* lazy import semantic diffusion
* lazy imports
* lazy import stable diffusion
* move sd output to its own module
* clean up
* lazy import t2iadapter
* lazy import unclip
* lazy import versatile and vq diffsuion
* lazy import vq diffusion
* helper to fetch objects from modules
* lazy import sdxl
* lazy import txt2vid
* lazy import stochastic karras
* fix model imports
* fix bug
* lazy import
* clean up
* clean up
* fixes for tests
* fixes for tests
* clean up
* remove import of torch_utils from utils module
* clean up
* clean up
* fix mistake import statement
* dedicated modules for exporting and loading
* remove testing utils from utils module
* fixes from merge conflicts
* Update src/diffusers/pipelines/kandinsky2_2/__init__.py
* fix docs
* fix alt diffusion copied from
* fix check dummies
* fix more docs
* remove accelerate import from utils module
* add type checking
* make style
* fix check dummies
* remove torch import from xformers check
* clean up error message
* fixes after upstream merges
* dummy objects fix
* fix tests
* remove unused module import
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Co-authored-by: Patrick von Platen <patrick.v.platen@gmail.com>