Explanation:

The method readlines() reads until EOF using readline() and returns a list containing the lines. If the optional sizehint argument is present, instead of reading up to EOF, whole lines totalling approximately sizehint bytes (possibly after rounding up to an internal buffer size) are read.
Syntax
Following is the syntax for readlines() method:
fileObject.readlines( sizehint );
Parameters
sizehint — This is the number of bytes to be read from the file.