python - Condensing Repetitive Code -

i created simple application loads multiple csv's , stores them lists.

import csv import collections  list1=[] list2=[] list3=[]   l = open("file1.csv") n = open("file2.csv") m = open("file3.csv")  csv_l = csv.reader(l) csv_n = csv.reader(n) csv_p = csv.reader(m)  row in csv_l:     list1.append(row)  row in csv_n:     list2.append(row)  row in csv_p:     list3.append(row)  l.close() n.close() m.close() 

i wanted create function responsible this, avoid being repetitive , clean code thinking this.

def read(filename):     x = open(filename)     y = csv.reader(x)     row in y:         list1.append(row)     x.close() 

however gets tough me when loop appends list. work append 1 list, if pass file name function append same list. not sure best way go this.

you need create new list each time, , return function:

def read(filename):     rows = []     x = open(filename)     y = csv.reader(x)     row in y:         rows.append(row)     x.close()     return rows 

then call follows

list1 = read("file1.csv") 

another option pass list in argument function - can choose whether create new list each time, or append multiple csvs same list:

def read(filename, rows):     x = open(filename)     y = csv.reader(x)     row in y:         rows.append(row)     x.close()     return rows  # 1 list per file: list1 = [] read("file1.csv", list1)  # multiple files combined 1 list: listcombined = [] read("file2.csv", listcombined) read("file3.csv", listcombined) 

i have used original code in answer, see malik brahimi's answer better way write function body using with , list(), , dogweather's comments - there lots of different choices here!