for large arraysthis in-place modification runs about percent faster than the code that creates new array with generator expression notes the arrays created by this module are not suitable for numeric work such as matrix or vector math for examplethe addition operator doesn' add the corresponding elements of the arraysinsteadit appends one array to the other to create storage and calculation efficient arraysuse the numpy extension available at the +operator can be used to append the contents of another array the *operator can be used to repeat an array see alsostruct ( bisect the bisect module provides support for keeping lists in sorted order it uses bisection algorithm to do most of its work bisect(listitem [low [high]]returns the index of the insertion point for item to be placed in list in order to maintain list in sorted order low and high are indices specifying subset of the list to examine if items is already in the listthe insertion point will always be to the right of existing entries in the list bisect_left(listitem [low [high]]returns the index of the insertion point for item to be placed in list in order to maintain list in sorted order low and high are indices specifying subset of the list to examine if items is already in the listthe insertion point will always be to the left of existing entries in the list bisect_right(listitem [low [high]]the same as bisect(insort(listitem [low [high]]inserts item into list in sorted order if item is already in the listthe new entry is inserted to the right of any existing entries insort_left(listitem [low [high]]inserts item into list in sorted order if item is already in the listthe new entry is inserted to the left of any existing entries insort_right(listitem [low [high]]the same as insort( lib fl ff