If we include all header files in C/Python, does it make the program bigger in size or slower in speed even if we are not with any functions in it?

[Patryk]

Hello everyone, I have a little problem, I hope you can help me, if we include all header files in c/python, does it make the program bigger in size or slower in speed even if we are not with any functions in it? Thank you for your answer and please do not ignore my subject.