Using the mmap module allows the user to randomly access locations in a file by mapping the file into memory. This is an alternative to using normal file operations.
import mmap
with open('filename.ext', 'r') as fd: # 0: map the whole file mm = mmap.mmap(fd.fileno(), 0)
# print characters at indices 5 through 10 print mm[5:10]
# print the line starting from mm's current position print mm.readline()
# write a character to the 5th index mm[5] = 'a'
# return mm's position to the beginning of the file mm.seek(0)
# close the mmap object mm.close()
Replacing text in a file
import fileinput
replacements = {'Search1': 'Replace1', 'Search2': 'Replace2'}
for line in fileinput.input('filename.txt', inplace=True):
for search_for in replacements:
replace_with = replacements[search_for] line = line.replac
