Reading And Writing Files

Exercise: Reading And Writing Files

What is the purpose of the os.path.basename() function?

Returns the base name of a file or directory

Returns the absolute path of a file

Checks if a path is a regular file

Deletes a file

Answer: A

os.path.basename() returns the base name of a file or directory.

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How can you read and print the lines containing numbers from a file named "text.txt"?

lines = open("text.txt").readlines()
for line in lines:
    if any(char.isdigit() for char in line):
        print(line)

read_numeric_lines("text.txt")

with open("text.txt", "r") as file:
    print(file.read("\d+"))

with open("text.txt", "r") as file:
    for line in file:
        if line.isdigit():
            print(line)

Answer: A

Using any() and isdigit() to filter and print lines containing numbers.

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How can you create a new directory named "my_directory"?

os.newdir("my_directory")

os.create_dir("my_directory")

os.mkdir("my_directory")

new_directory("my_directory")

Answer: C

The os.mkdir() function is used to create a new directory in Python.

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What does the file.tell() method return?

Returns the file's absolute path

Returns the size of a file in bytes

Returns the current position of the file cursor

Returns the file's creation time

Answer: C

The tell() method returns the current position of the file cursor.

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How can you write a list of dictionaries to a CSV file named "data.csv"?

write_csv("data.csv", [{"key1": "value1"}, {"key2": "value2"}])

with open("data.csv", "w") as file:
    write_csv(file, [{"key1": "value1"}, {"key2": "value2"}])

csv.write("data.csv", [{"key1": "value1"}, {"key2": "value2"}])

with open("data.csv", "w") as file:
    csv.writer(file).writerow([{"key1", "value1"}, {"key2", "value2"}])

Answer: B

Using a context manager to open the file and writing a list of dictionaries to a CSV file.

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