In this Python 2.7 Tutorial I focus on how to work with files in Python 2.7. Specifically I show you how to:

• Open a file and access its contents
• Break file content up into pieces and analyze it
• Sort file information
• Write information back to a file
• Search for files in a directory
• Create and Delete directories

Like always, a lot of code follows the video. If you have any questions or comments leave them below. And, if you missed my other Python Tutorials they are available here:

• Python 2.7 Tutorial Pt 1 : Importing Modules and variable types
• Python 2.7 Tutorial Pt 2: Python Lists & Tuples
• Python 2.7 Tutorial Pt 3: The Print Function & Dictionaries
• Python 2.7 Tutorial Pt 4: The IF Statement & Conditional Expression
• Python 2.7 Tutorial Pt 5: Looping with While and For
• Python 2.7 Tutorial Pt 6: Python Functions
• Python 2.7 Tutorial Pt 7: Python Object Oriented Programming Pt 1
• Python 2.7 Tutorial Pt 8: Python Object Oriented Programming Pt 2
• Python 2.7 Tutorial Pt 9: Python Exception Handling

Here is All the Code from the Video

It is heavily commented, but leave questions below if anything is confusing.

#! /usr/bin/python

import os

def retrieveFile():
# Will catch any errors triggered if the file doesn’t exist
try:
bestStudent = {}
bestStudentStr = “The Best Students Ranked\n\n”

# Will open the file studentgrades.txt and store it in the file f
f = open(‘studentgrades.txt’)

# If the file isn’t found a friendly error will print to screen
except(IOError), e:
print “File not found”, e
else:

# Splits each line in the file into 2 strings
# Creates a dictionary using those 2 strings as key value pairs
for line in f:
name, grade = line.split()
bestStudent[grade] = name

# Closes the file
f.close()

# Sorts the grades from highest to lowest and stores them in a new string
for i in sorted(bestStudent.keys(), reverse = True):
print(bestStudent[i] + ‘ scored a ‘ + i)
bestStudentStr += bestStudent[i] + ‘ scored a ‘ + i + “\n”

print(“\n”)

print bestStudentStr

# Outputs the string to a new file ‘w’ stands for write to file
outToFile = open(‘studentrank.txt’, ‘w’)
outToFile.write(bestStudentStr)

# Closes the created file
outToFile.close()

print(‘Finished Update’)

return

def directoryPlay():

# Outputs the files stored in directory /usr
print os.listdir(“/usr”)

# Checks if /usr/bin/python is a directory and then a file
print os.path.isdir(“/usr/bin/python”)
print os.path.isfile(“/usr/bin/python”)

# Outputs all files in directory /usr
dirList = os.listdir(“/usr”)

# Cycles through files in /usr and outputs files if one of them is a directory
for file in dirList:
if os.path.isdir(“/usr/”+file):
print os.listdir(“/usr/”+file)
else:
continue

# How to create a new directory and then how to delete it
os.mkdir(“/Users/derekbanas/Documents/Testing”)
os.rmdir(“/Users/derekbanas/Documents/Testing”) # Works if program has permission

return

def main():
retrieveFile()
directoryPlay()

if __name__ == ‘__main__’: main()