Answers for "how to read the text file line by line and select some character from the line in python"

python read file line by line

with open("file.txt") as file_in:
    lines = []
    for line in file_in:
        lines.append(line)

how to read a text file line by line in python

# Open the file with read only permit
f = open('my_text_file.txt')
# use readline() to read the first line 
line = f.readline()
# use the read line to read further.
# If the file is not empty keep reading one line
# at a time, till the file is empty
while line:
    # in python 2+
    # print line
    # in python 3 print is a builtin function, so
    print(line)
    # use realine() to read next line
    line = f.readline()
f.close()