Understanding the use of open() function in Python

In Python, the open() function is the correct and standard way to open a file. This function returns a file object, which would then be used to read, write and manipulate the file.

The syntax of the open() function is quite simple:

file = open('filename', 'mode')

In the syntax above, 'filename' is a string that indicates the name of the file that you want to access, and 'mode' is an optional string that defines which mode you want to open the file in. A few common modes include:

• 'r' -> Open a file for reading. (default)
• 'w' -> Open a file for writing.
• 'a' -> Open a file for appending.
• 'b' -> To open in binary mode.
• '+' -> To open a file for updating (reading and writing).

Here is an example of using the open() function in Python:

file = open('test.txt', 'r')
content = file.read()
print(content)
file.close()

In the above example, the 'test.txt' file is opened in read mode (‘r’), the content is read from the file, printed on the screen, and then the file is closed with file.close(). It is good practice to close the file after you are done with it to free up system resources.

Though the open() function is a straightforward and easy way to perform file operations, Python also provides with us with statement which automatically takes care of closing the file once done, thus giving a more efficient way to handle files.

Remember, to perform read or write operations, a file must first be opened correctly using the open() function. Other functions like read() or write() are used after a file is successfully opened for reading or writing respectively and cannot open files by themselves. The create() function mentioned in the options does not exist in Python.