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Writing to CSV from String or List

Writing to a .csv file is not unlike writing to a regular file in most regards, and is fairly straightforward. I will, to the best of my ability, cover the easiest, and most efficient approach to the problem.

import csv
#------ We will write to CSV in this function ------------
def csv_writer(data, path):
#Open CSV file whose path we passed.
with open(path, "wb") as csv_file:
writer = csv.writer(csv_file, delimiter=',')
for line in data:
writer.writerow(line)
#---- Define our list here, and call function ------------
if __name__ == "__main__":
"""
data = our list that we want to write.
Split it so we get a list of lists.
"""
data = ["first_name,last_name,age".split(","),
"John,Doe,22".split(","),
"Jane,Doe,31".split(","),
"Jack,Reacher,27".split(",")
]
# Path to CSV file we want to write to.
path = "output.csv"
csv_writer(data, path)

Appending a String as a newline in a CSV file

Section titled “Appending a String as a newline in a CSV file”
def append_to_csv(input_string):
with open("fileName.csv", "a") as csv_file:
csv_file.write(input_row + "\n")

|Parameter|Details |---|---|---|---|---|---|---|---|---|--- |open (“/path/”, “mode”)|Specify the path to your CSV file |open (path, “mode”)|Specify mode to open file in (read, write, etc.) |csv.writer(file, delimiter)|Pass opened CSV file here |csv.writer(file, delimiter=’ ’)|Specify delimiter character or pattern

open( path, "wb")

"wb" - Write mode.

The b parameter in "wb" we have used, is necessary only if you want to open it in binary mode, which is needed only in some operating systems like Windows.

csv.writer ( csv_file, delimiter=',' )

Here the delimiter we have used, is ,, because we want each cell of data in a row, to contain the first name, last name, and age respectively. Since our list is split along the , too, it proves rather convenient for us.