Python programs often seem to "hang" in the beginning. This is due to heavy modules being imported. This package lets the user know what is happening, to avoid this impression:
pip install preload
This will get you the
from preload import preload
preload(["matplotlib.pyplot", "scipy.signal"])
# Rest of your imports and code, such as:
import numpy as np
import scipy.signal
import matplotlib.pyplot as plt
print("Hello")