Added initial support for basic context windows - in progress

This commit is contained in:
Jedrzej Kosinski 2025-08-04 20:22:30 -07:00
parent 03895dea7c
commit b14b4a64ae
4 changed files with 548 additions and 2 deletions

488
comfy/context_windows.py Normal file
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@ -0,0 +1,488 @@
from __future__ import annotations
from typing import TYPE_CHECKING, Callable
import torch
import numpy as np
import collections
from abc import ABC, abstractmethod
import logging
import comfy.model_management
if TYPE_CHECKING:
from comfy.model_base import BaseModel
from comfy.controlnet import ControlBase
class ContextWindowABC(ABC):
def __init__(self):
...
@abstractmethod
def get_tensor(self, full: torch.Tensor) -> torch.Tensor:
"""
Get torch.Tensor applicable to current window.
"""
raise NotImplementedError("Not implemented.")
@abstractmethod
def add_window(self, full: torch.Tensor, to_window: torch.Tensor) -> torch.Tensor:
"""
Apply torch.Tensor of window to the full tensor, in place. Returns reference to updated full tensor, not a copy.
"""
raise NotImplementedError("Not implemented.")
class ContextHandlerABC(ABC):
def __init__(self):
...
@abstractmethod
def should_use_context(self, model: BaseModel, conds: list[list[dict]], x_in: torch.Tensor, timestep: torch.Tensor, model_options: dict[str]) -> bool:
raise NotImplementedError("Not implemented.")
@abstractmethod
def get_resized_cond(self, cond_in: list[dict], x_in: torch.Tensor, window: ContextWindowABC, device=None) -> list:
raise NotImplementedError("Not implemented.")
@abstractmethod
def execute(self, calc_cond_batch: Callable, model: BaseModel, conds: list[list[dict]], x_in: torch.Tensor, timestep: torch.Tensor, model_options: dict[str]):
raise NotImplementedError("Not implemented.")
class IndexListContextWindow(ContextWindowABC):
def __init__(self, index_list: list[int], dim: int=0):
self.index_list = index_list
self.context_length = len(index_list)
self.dim = dim
def get_tensor(self, full: torch.Tensor, device=None, dim=None) -> torch.Tensor:
if dim is None:
dim = self.dim
if dim == 0:
return full[self.index_list].to(device)
else:
return full[:, self.index_list].to(device)
def add_window(self, full: torch.Tensor, to_window: torch.Tensor, dim=None) -> torch.Tensor:
if dim is None:
dim = self.dim
if dim == 0:
full[self.index_list] += to_window
else:
full[:, self.index_list] += to_window
return full
ContextResults = collections.namedtuple("ContextResults", ['window_idx', 'sub_conds_out', 'sub_conds', 'window'])
class IndexListContextHandler(ContextHandlerABC):
def __init__(self, context_schedule: str, fuse_method: str, context_length: int=1, context_overlap: int=0, dim=0):
self.context_schedule = context_schedule
self.fuse_method = fuse_method
self.context_length = context_length
self.context_overlap = context_overlap
self.context_stride = 1
self.closed_loop = False
self.step = 0 # TODO: get from model options
self.dim = dim
def should_use_context(self, model: BaseModel, conds: list[list[dict]], x_in: torch.Tensor, timestep: torch.Tensor, model_options: dict[str]) -> bool:
# for now, assume first dim is batch - should have stored on BaseModel in actual implementation
if x_in.size(0) > self.context_length:
logging.info(f"Using context windows {self.context_length} for {x_in.size(0)} frames.")
return True
return False
def prepare_control_objects(self, control: ControlBase, device=None) -> ControlBase:
if device is not None:
control = control.get_instance_for_device(device)
if control.previous_controlnet is not None:
self.prepare_control_objects(control.previous_controlnet, device)
return control
def get_resized_cond(self, cond_in: list[dict], x_in: torch.Tensor, window: IndexListContextWindow, device=None) -> list:
if cond_in is None:
return None
# reuse or resize cond items to match context requirements
resized_cond = []
# cond object is a list containing a dict - outer list is irrelevant, so just loop through it
for actual_cond in cond_in:
resized_actual_cond = actual_cond.copy()
# now we are in the inner dict - "pooled_output" is a tensor, "control" is a ControlBase object, "model_conds" is dictionary
for key in actual_cond:
try:
cond_item = actual_cond[key]
if isinstance(cond_item, torch.Tensor):
# check that tensor is the expected length - x.size(0)
if cond_item.size(0) == x_in.size(0):
# if so, it's subsetting time - tell controls the expected indeces so they can handle them
actual_cond_item = window.get_tensor(cond_item)
resized_actual_cond[key] = actual_cond_item.to(device)
else:
resized_actual_cond[key] = cond_item.to(device)
# look for control
elif key == "control":
resized_actual_cond[key] = self.prepare_control_objects(cond_item, device)
elif isinstance(cond_item, dict):
new_cond_item = cond_item.copy()
# when in dictionary, look for tensors and CONDCrossAttn [comfy/conds.py] (has cond attr that is a tensor)
for cond_key, cond_value in new_cond_item.items():
if isinstance(cond_value, torch.Tensor):
if cond_value.size(0) == x_in.size(0):
new_cond_item[cond_key] = window.get_tensor(cond_value, device)
# if has cond that is a Tensor, check if needs to be subset
elif hasattr(cond_value, "cond") and isinstance(cond_value.cond, torch.Tensor):
if cond_value.cond.size(0) == x_in.size(0):
new_cond_item[cond_key] = cond_value._copy_with(window.get_tensor(cond_value.cond, device))
elif cond_key == "num_video_frames": # for SVD
new_cond_item[cond_key] = cond_value._copy_with(cond_value.cond)
new_cond_item[cond_key].cond = window.context_length
resized_actual_cond[key] = new_cond_item
else:
resized_actual_cond[key] = cond_item
finally:
del cond_item # just in case to prevent VRAM issues
resized_cond.append(resized_actual_cond)
return resized_cond
def get_context_windows(self, model: BaseModel, x_in: torch.Tensor, model_options: dict[str]) -> list[IndexListContextWindow]:
full_length = x_in.size(0) # TODO: choose dim based on model
context_windows = get_context_windows(full_length, self, model_options)
context_windows = [IndexListContextWindow(window, dim=self.dim) for window in context_windows]
return context_windows
def execute(self, calc_cond_batch: Callable, model: BaseModel, conds: list[list[dict]], x_in: torch.Tensor, timestep: torch.Tensor, model_options: dict[str]):
context_windows = self.get_context_windows(model, x_in, model_options)
enumerated_context_windows = list(enumerate(context_windows))
conds_final = [torch.zeros_like(x_in) for _ in conds]
if self.fuse_method == ContextFuseMethod.RELATIVE:
counts_final = [torch.ones((x_in.shape[0], 1, 1, 1), device=x_in.device) for _ in conds]
else:
counts_final = [torch.zeros((x_in.shape[0], 1, 1, 1), device=x_in.device) for _ in conds]
biases_final = [([0.0] * x_in.shape[0]) for _ in conds]
for enum_window in enumerated_context_windows:
results = self.evaluate_context_windows(calc_cond_batch, model, x_in, conds, timestep, [enum_window], model_options)
for result in results:
self.combine_context_window_results(x_in, result.sub_conds_out, result.sub_conds, result.window, result.window_idx, len(enumerated_context_windows), timestep,
conds_final, counts_final, biases_final)
# finalize conds
if self.fuse_method == ContextFuseMethod.RELATIVE:
# relative is already normalized, so return as is
del counts_final
return conds_final
else:
# normalize conds via division by context usage counts
for i in range(len(conds_final)):
conds_final[i] /= counts_final[i]
del counts_final
return conds_final
def evaluate_context_windows(self, calc_cond_batch: Callable, model: BaseModel, x_in: torch.Tensor, conds, timestep: torch.Tensor, enumerated_context_windows: list[tuple[int, IndexListContextWindow]],
model_options, device=None, first_device=None):
results: list[ContextResults] = []
for window_idx, window in enumerated_context_windows:
# allow processing to end between context window executions for faster Cancel
comfy.model_management.throw_exception_if_processing_interrupted()
# if device is None:
# # non-MultiGPU execution
# comfy.model_management.throw_exception_if_processing_interrupted()
# elif first_device == device:
# # MultiGPU execution
# try:
# comfy.model_management.throw_exception_if_processing_interrupted()
# if ADGS.is_processing_interrupted():
# break
# except comfy.model_management.InterruptProcessingException:
# ADGS.interrupt_processing()
# break
# else:
# # MultiGPU execution
# if ADGS.is_processing_interrupted():
# break
# ADGS.params.sub_idxs = ctx_idxs
# if device is None:
# motion_models_devices = ADGS.motion_models_devices.values()
# else:
# motion_models_devices = ADGS.motion_models_devices.get(device, None)
# if motion_models_devices is None:
# motion_models_devices = []
# else:
# motion_models_devices = [motion_models_devices]
# model = ADGS.model_patcher_devices[device].model
# for motion_models in motion_models_devices:
# motion_models.set_sub_idxs(ctx_idxs)
# motion_models.set_video_length(len(ctx_idxs), ADGS.params.full_length)
# update exposed params
model_options["transformer_options"]["context_window"] = window
# model_options["transformer_options"]["ad_params"]["sub_idxs"] = ctx_idxs
# model_options["transformer_options"]["ad_params"]["context_length"] = len(ctx_idxs)
# get subsections of x, timestep, conds
sub_x = window.get_tensor(x_in, device)
sub_timestep = window.get_tensor(timestep, device, dim=0)
sub_conds = [self.get_resized_cond(cond, x_in, window, device) for cond in conds]
# CREF.prepare_referencecn(ctx_idxs, window_idx, model_options)
sub_conds_out = calc_cond_batch(model, sub_conds, sub_x, sub_timestep, model_options)
if device is not None:
for i in range(len(sub_conds_out)):
sub_conds_out[i] = sub_conds_out[i].to(x_in.device)
results.append(ContextResults(window_idx, sub_conds_out, sub_conds, window))
return results
def combine_context_window_results(self, x_in: torch.Tensor, sub_conds_out, sub_conds, window: IndexListContextWindow, window_idx: int, total_windows: int, timestep: torch.Tensor,
conds_final: list[torch.Tensor], counts_final: list[torch.Tensor], biases_final: list[torch.Tensor]):
if self.fuse_method == ContextFuseMethod.RELATIVE:
for pos, idx in enumerate(window.index_list):
# bias is the influence of a specific index in relation to the whole context window
bias = 1 - abs(idx - (window.index_list[0] + window.index_list[-1]) / 2) / ((window.index_list[-1] - window.index_list[0] + 1e-2) / 2)
bias = max(1e-2, bias)
# take weighted average relative to total bias of current idx
for i in range(len(sub_conds_out)):
bias_total = biases_final[i][idx]
prev_weight = (bias_total / (bias_total + bias))
new_weight = (bias / (bias_total + bias))
# TODO: account for dim not being 0
conds_final[i][idx] = conds_final[i][idx] * prev_weight + sub_conds_out[i][pos] * new_weight
biases_final[i][idx] = bias_total + bias
else:
# add conds and counts based on weights of fuse method; TODO: account for dim not being 0
weights = get_context_weights(window.context_length, x_in.shape[0], window.index_list, self, sigma=timestep)
weights_tensor = torch.Tensor(weights).to(device=x_in.device).unsqueeze(-1).unsqueeze(-1).unsqueeze(-1)
for i in range(len(sub_conds_out)):
window.add_window(conds_final[i], sub_conds_out[i] * weights_tensor)
window.add_window(counts_final[i], weights_tensor)
# # handle NaiveReuse
# NAIVE.cache_first_context_results(window_idx, ctx_idxs, sub_conds, conds_final, counts_final)
# # handle ContextRef
# CREF.finalize_step()
class ContextSchedules:
UNIFORM_LOOPED = "looped_uniform"
UNIFORM_STANDARD = "standard_uniform"
STATIC_STANDARD = "standard_static"
BATCHED = "batched"
# from https://github.com/neggles/animatediff-cli/blob/main/src/animatediff/pipelines/context.py
def create_windows_uniform_looped(num_frames: int, handler: IndexListContextHandler, model_options: dict[str]):
windows = []
if num_frames < handler.context_length:
windows.append(list(range(num_frames)))
return windows
context_stride = min(handler.context_stride, int(np.ceil(np.log2(num_frames / handler.context_length))) + 1)
# obtain uniform windows as normal, looping and all
for context_step in 1 << np.arange(context_stride):
pad = int(round(num_frames * ordered_halving(handler.step)))
for j in range(
int(ordered_halving(handler.step) * context_step) + pad,
num_frames + pad + (0 if handler.closed_loop else -handler.context_overlap),
(handler.context_length * context_step - handler.context_overlap),
):
windows.append([e % num_frames for e in range(j, j + handler.context_length * context_step, context_step)])
return windows
def create_windows_uniform_standard(num_frames: int, handler: IndexListContextHandler, model_options: dict[str]):
# unlike looped, uniform_straight does NOT allow windows that loop back to the beginning;
# instead, they get shifted to the corresponding end of the frames.
# in the case that a window (shifted or not) is identical to the previous one, it gets skipped.
windows = []
if num_frames <= handler.context_length:
windows.append(list(range(num_frames)))
return windows
context_stride = min(handler.context_stride, int(np.ceil(np.log2(num_frames / handler.context_length))) + 1)
# first, obtain uniform windows as normal, looping and all
for context_step in 1 << np.arange(context_stride):
pad = int(round(num_frames * ordered_halving(handler.step)))
for j in range(
int(ordered_halving(handler.step) * context_step) + pad,
num_frames + pad + (-handler.context_overlap),
(handler.context_length * context_step - handler.context_overlap),
):
windows.append([e % num_frames for e in range(j, j + handler.context_length * context_step, context_step)])
# now that windows are created, shift any windows that loop, and delete duplicate windows
delete_idxs = []
win_i = 0
while win_i < len(windows):
# if window is rolls over itself, need to shift it
is_roll, roll_idx = does_window_roll_over(windows[win_i], num_frames)
if is_roll:
roll_val = windows[win_i][roll_idx] # roll_val might not be 0 for windows of higher strides
shift_window_to_end(windows[win_i], num_frames=num_frames)
# check if next window (cyclical) is missing roll_val
if roll_val not in windows[(win_i+1) % len(windows)]:
# need to insert new window here - just insert window starting at roll_val
windows.insert(win_i+1, list(range(roll_val, roll_val + handler.context_length)))
# delete window if it's not unique
for pre_i in range(0, win_i):
if windows[win_i] == windows[pre_i]:
delete_idxs.append(win_i)
break
win_i += 1
# reverse delete_idxs so that they will be deleted in an order that doesn't break idx correlation
delete_idxs.reverse()
for i in delete_idxs:
windows.pop(i)
return windows
def create_windows_static_standard(num_frames: int, handler: IndexListContextHandler, model_options: dict[str]):
windows = []
if num_frames <= handler.context_length:
windows.append(list(range(num_frames)))
return windows
# always return the same set of windows
delta = handler.context_length - handler.context_overlap
for start_idx in range(0, num_frames, delta):
# if past the end of frames, move start_idx back to allow same context_length
ending = start_idx + handler.context_length
if ending >= num_frames:
final_delta = ending - num_frames
final_start_idx = start_idx - final_delta
windows.append(list(range(final_start_idx, final_start_idx + handler.context_length)))
break
windows.append(list(range(start_idx, start_idx + handler.context_length)))
return windows
def create_windows_batched(num_frames: int, handler: IndexListContextHandler, model_options: dict[str]):
windows = []
if num_frames <= handler.context_length:
windows.append(list(range(num_frames)))
return windows
# always return the same set of windows;
# no overlap, just cut up based on context_length;
# last window size will be different if num_frames % opts.context_length != 0
for start_idx in range(0, num_frames, handler.context_length):
windows.append(list(range(start_idx, min(start_idx + handler.context_length, num_frames))))
return windows
def create_windows_default(num_frames: int, handler: IndexListContextHandler):
return [list(range(num_frames))]
def get_context_windows(num_frames: int, handler: IndexListContextHandler, model_options: dict[str]) -> list[list[int]]:
context_func = CONTEXT_MAPPING.get(handler.context_schedule, None)
if not context_func:
raise ValueError(f"Unknown context_schedule '{handler.context_schedule}'.")
return context_func(num_frames, handler, model_options)
CONTEXT_MAPPING = {
ContextSchedules.UNIFORM_LOOPED: create_windows_uniform_looped,
ContextSchedules.UNIFORM_STANDARD: create_windows_uniform_standard,
ContextSchedules.STATIC_STANDARD: create_windows_static_standard,
ContextSchedules.BATCHED: create_windows_batched,
}
def get_context_weights(length: int, full_length: int, idxs: list[int], handler: IndexListContextHandler, sigma: torch.Tensor=None):
weights_func = FUSE_MAPPING.get(handler.fuse_method, None)
if not weights_func:
raise ValueError(f"Unknown fuse_method '{handler.fuse_method}'.")
return weights_func(length, sigma=sigma, handler=handler, full_length=full_length, idxs=idxs)
def create_weights_flat(length: int, **kwargs) -> list[float]:
# weight is the same for all
return [1.0] * length
def create_weights_pyramid(length: int, **kwargs) -> list[float]:
# weight is based on the distance away from the edge of the context window;
# based on weighted average concept in FreeNoise paper
if length % 2 == 0:
max_weight = length // 2
weight_sequence = list(range(1, max_weight + 1, 1)) + list(range(max_weight, 0, -1))
else:
max_weight = (length + 1) // 2
weight_sequence = list(range(1, max_weight, 1)) + [max_weight] + list(range(max_weight - 1, 0, -1))
return weight_sequence
def create_weights_overlap_linear(length: int, full_length: int, idxs: list[int], handler: IndexListContextHandler, **kwargs):
# based on code in Kijai's WanVideoWrapper: https://github.com/kijai/ComfyUI-WanVideoWrapper/blob/dbb2523b37e4ccdf45127e5ae33e31362f755c8e/nodes.py#L1302
# only expected overlap is given different weights
weights_torch = torch.ones((length))
# blend left-side on all except first window
if min(idxs) > 0:
ramp_up = torch.linspace(1e-37, 1, handler.context_overlap)
weights_torch[:handler.context_overlap] = ramp_up
# blend right-side on all except last window
if max(idxs) < full_length-1:
ramp_down = torch.linspace(1, 1e-37, handler.context_overlap)
weights_torch[-handler.context_overlap:] = ramp_down
return weights_torch
class ContextFuseMethod:
FLAT = "flat"
PYRAMID = "pyramid"
RELATIVE = "relative"
OVERLAP_LINEAR = "overlap-linear"
LIST = [PYRAMID, FLAT, OVERLAP_LINEAR]
LIST_STATIC = [PYRAMID, RELATIVE, FLAT, OVERLAP_LINEAR]
FUSE_MAPPING = {
ContextFuseMethod.FLAT: create_weights_flat,
ContextFuseMethod.PYRAMID: create_weights_pyramid,
ContextFuseMethod.RELATIVE: create_weights_pyramid,
ContextFuseMethod.OVERLAP_LINEAR: create_weights_overlap_linear,
}
# Returns fraction that has denominator that is a power of 2
def ordered_halving(val):
# get binary value, padded with 0s for 64 bits
bin_str = f"{val:064b}"
# flip binary value, padding included
bin_flip = bin_str[::-1]
# convert binary to int
as_int = int(bin_flip, 2)
# divide by 1 << 64, equivalent to 2**64, or 18446744073709551616,
# or b10000000000000000000000000000000000000000000000000000000000000000 (1 with 64 zero's)
return as_int / (1 << 64)
def get_missing_indexes(windows: list[list[int]], num_frames: int) -> list[int]:
all_indexes = list(range(num_frames))
for w in windows:
for val in w:
try:
all_indexes.remove(val)
except ValueError:
pass
return all_indexes
def does_window_roll_over(window: list[int], num_frames: int) -> tuple[bool, int]:
prev_val = -1
for i, val in enumerate(window):
val = val % num_frames
if val < prev_val:
return True, i
prev_val = val
return False, -1
def shift_window_to_start(window: list[int], num_frames: int):
start_val = window[0]
for i in range(len(window)):
# 1) subtract each element by start_val to move vals relative to the start of all frames
# 2) add num_frames and take modulus to get adjusted vals
window[i] = ((window[i] - start_val) + num_frames) % num_frames
def shift_window_to_end(window: list[int], num_frames: int):
# 1) shift window to start
shift_window_to_start(window, num_frames)
end_val = window[-1]
end_delta = num_frames - end_val - 1
for i in range(len(window)):
# 2) add end_delta to each val to slide windows to end
window[i] = window[i] + end_delta

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@ -16,6 +16,7 @@ import comfy.sampler_helpers
import comfy.model_patcher
import comfy.patcher_extension
import comfy.hooks
import comfy.context_windows
import scipy.stats
import numpy
@ -198,14 +199,20 @@ def finalize_default_conds(model: 'BaseModel', hooked_to_run: dict[comfy.hooks.H
hooked_to_run.setdefault(p.hooks, list())
hooked_to_run[p.hooks] += [(p, i)]
def calc_cond_batch(model: 'BaseModel', conds: list[list[dict]], x_in: torch.Tensor, timestep, model_options):
def calc_cond_batch(model: BaseModel, conds: list[list[dict]], x_in: torch.Tensor, timestep, model_options: dict[str]):
handler: comfy.context_windows.ContextHandlerABC = model_options.get("context_handler", None)
if handler is None or not handler.should_use_context(model, conds, x_in, timestep, model_options):
return _calc_cond_batch_outer(model, conds, x_in, timestep, model_options)
return handler.execute(_calc_cond_batch_outer, model, conds, x_in, timestep, model_options)
def _calc_cond_batch_outer(model: BaseModel, conds: list[list[dict]], x_in: torch.Tensor, timestep, model_options):
executor = comfy.patcher_extension.WrapperExecutor.new_executor(
_calc_cond_batch,
comfy.patcher_extension.get_all_wrappers(comfy.patcher_extension.WrappersMP.CALC_COND_BATCH, model_options, is_model_options=True)
)
return executor.execute(model, conds, x_in, timestep, model_options)
def _calc_cond_batch(model: 'BaseModel', conds: list[list[dict]], x_in: torch.Tensor, timestep, model_options):
def _calc_cond_batch(model: BaseModel, conds: list[list[dict]], x_in: torch.Tensor, timestep, model_options):
out_conds = []
out_counts = []
# separate conds by matching hooks

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@ -0,0 +1,50 @@
from __future__ import annotations
from comfy_api.latest import ComfyExtension, io
import comfy.context_windows
class ContextWindowsNode(io.ComfyNode):
@classmethod
def define_schema(cls) -> io.Schema:
return io.Schema(
node_id="ContexWindowsTest",
display_name="Context Windows Test",
category="context",
description="Test node for context windows",
inputs=[
io.Model.Input("model", tooltip="The model to apply context windows to during sampling."),
io.Int.Input("context_length", min=1, default=1, tooltip="The length of the context window."),
io.Int.Input("context_overlap", min=0, default=0, tooltip="The overlap of the context window."),
io.Combo.Input("context_schedule", options=[
comfy.context_windows.ContextSchedules.STATIC_STANDARD,
comfy.context_windows.ContextSchedules.BATCHED,
], tooltip="The stride of the context window."),
io.Combo.Input("fuse_method", options=comfy.context_windows.ContextFuseMethod.LIST_STATIC,default=comfy.context_windows.ContextFuseMethod.PYRAMID, tooltip="The method to use to fuse the context windows."),
io.Int.Input("dim", min=0, max=1, default=0, tooltip="The dimension to apply the context windows to."),
],
outputs=[
io.Model.Output(tooltip="The model with context windows applied during sampling."),
],
is_experimental=True,
)
@classmethod
def execute(cls, model: io.Model.Type, context_length: int, context_overlap: int, context_schedule: str, fuse_method: str, dim: int) -> io.Model:
model = model.clone()
model.model_options["context_handler"] = comfy.context_windows.IndexListContextHandler(
context_schedule=context_schedule,
fuse_method=fuse_method,
context_length=context_length,
context_overlap=context_overlap,
dim=dim)
return io.NodeOutput(model)
class ContextWindowsExtension(ComfyExtension):
async def get_node_list(self) -> list[type[io.ComfyNode]]:
return [
ContextWindowsNode,
]
def comfy_entrypoint():
return ContextWindowsExtension()

View File

@ -2320,6 +2320,7 @@ async def init_builtin_extra_nodes():
"nodes_camera_trajectory.py",
"nodes_edit_model.py",
"nodes_tcfg.py",
"nodes_context_windows.py",
]
import_failed = []