Search a text file and print related lines in Python?

by 
searchfile = open("file.txt", "r")
for line in searchfile:
    if "searchphrase" in line: print line
searchfile.close()

To print out multiple lines (in a simple way)

f = open("file.txt", "r")
searchlines = f.readlines()
f.close()
for i, line in enumerate(searchlines):
    if "searchphrase" in line: 
        for l in searchlines[i:i+3]: print l,
        print

The comma in print l, prevents extra spaces from appearing in the output; the trailing print statement demarcates results from different lines.

Or better yet (stealing back from Mark Ransom):

with open("file.txt", "r") as f:
    searchlines = f.readlines()
for i, line in enumerate(searchlines):
    if "searchphrase" in line: 
        for l in searchlines[i:i+3]: print l,
        print

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