Measures the amount of code loaded by "import X"

size_of_import.py

import os
import sys

original_modules = dict(sys.modules)

import pandas

sizes = {}
total = 0
files = set()
for name, module in sys.modules.items():
    if name in original_modules:
        continue
    if hasattr(module, "__file__"):
        filename = module.__file__
        files.add(filename)

for filename in files:
    stat = os.stat(filename)
    total += stat.st_size
    for package in ["pandas", "numpy", "matplotlib", "dateutil"]:
        if f"site-packages/{package}/" in filename:
            sizes.setdefault(package, 0)
            sizes[package] += stat.st_size
            break
    else:
        sizes.setdefault("stdlib", 0)
        sizes["stdlib"] += stat.st_size

print(total)
print(sizes)