could not find ffmpeg

[chitz1]

hello
im getting this error saying " Failed to parse NetParameter file: yolov3.weights in function 'cv::dnn::dnn4_v20190122::readNetFromDarknet'" and i am new to this deep learning could you please help me .
details
python real-time-audio.py
C:\Users\DELL\AppData\Local\Programs\Python\Python36\lib\site-packages\pydub\utils.py:165: RuntimeWarning: Couldn't find ffmpeg or avconv - defaulting to ffmpeg, but may not work
warn("Couldn't find ffmpeg or avconv - defaulting to ffmpeg, but may not work", RuntimeWarning)
[INFO] loading YOLO from disk...
Traceback (most recent call last):
File "real-time-audio.py", line 16, in
net = cv2.dnn.readNetFromDarknet("yolov3.cfg", "yolov3.weights")
cv2.error: OpenCV(4.1.0) C:\projects\opencv-python\opencv\modules\dnn\src\darknet\darknet_importer.cpp:214: error: (-212:Parsing error) Failed to parse NetParameter file: yolov3.weights in function 'cv::dnn::dnn4_v20190122::readNetFromDarknet'