python - How to read first line of a file twice? -

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i have big files many lines , want read first line first , loop through lines starting first line again.

i first thought it:

file = open("filename", 'r') first_line = file.readline() dostuff_1(first_line)  line in file:    dostuff_2(line)  file.close()

but issue script first line passed dostuff_2 second line , not first one. don't have intuition of kind of object file is. think iterator , don't know how deal it. bad solution found 

file = open("filename", 'r') first_line = file.readline()  count = 0 line in file:    if count == 0:       count = 1       dostuff_1(first_line)    dostuff_2(line)  file.close()

but pretty dumb , computationally bit costly runs if statement @ each iteration.

you this:

with open('filename', 'r') file:     first_line = file.readline()     dostuff_1(first_line)     dostuff_2(first_line)      # remaining lines     line in file:         dostuff_2(line)

note changed code use with file automatically closed.


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