How do I determine the size of an object in Python?

To determine the size of an object in Python, use sys.getsizeof() from the sys module. It measures the memory (in bytes) used by the object itself. For example:

import sys

data = [1, 2, 3]
print(sys.getsizeof(data)) # Outputs the size of the list

However, sys.getsizeof() doesn’t include memory used by elements inside collections (e.g., lists or dictionaries). For a complete size, use pympler:

from pympler import asizeof

data = [1, 2, [3, 4]]
print(asizeof.asizeof(data)) # Total memory usage

This helps optimize memory in programs by analyzing object sizes.