In this tutorial, you will learn to parse, read and write JSON in Python with the help of examples. Also, you will learn to convert JSON to dict and pretty print it. Java; C Tutorial. If you do not know how to read and write files in Python, we recommend you to check Python File I/O. Python Convert to JSON string. You can use this handle to read from or write to a file. Python treats the file as an object, which has its own attributes and methods. As you already read before, there are two types of flat files, text and binary files. What is a file? File is a named location on disk to store related information. It is used to permanently store data in a non-volatile memory (e.g. Since, random access memory (RAM) is volatile which loses its data when computer is turned off, we use files for future use of the data. When we want to read from or write to a file we need to open it first. When we are done, it needs to be closed, so that resources that are tied with the file are freed. Hence, in Python, a file operation takes place in the following order. • Open a file • Read or write (perform operation) • Close the file How to open a file? Python has a built-in function open() to open a file. Resident evil 2 ps2 rom. Download Resident Evil - Code - Veronica X ROM for Playstation 2(PS2 ISOs) and Play Resident Evil - Code - Veronica X Video Game on your PC, Mac, Android or iOS device! This function returns a file object, also called a handle, as it is used to read or modify the file accordingly. >>> f = open('test.txt') # open file in current directory >>> f = open('C:/Python33/README.txt') # specifying full path We can specify the mode while opening a file. In mode, we specify whether we want to read 'r', write 'w' or append 'a' to the file. We also specify if we want to open the file in text mode or binary mode. The default is reading in text mode. In this mode, we get strings when reading from the file. On the other hand, binary mode returns bytes and this is the mode to be used when dealing with non-text files like image or exe files. Python File Modes Mode Description 'r' Open a file for reading. (default) 'w' Open a file for writing. Creates a new file if it does not exist or truncates the file if it exists. 'x' Open a file for exclusive creation. If the file already exists, the operation fails. 'a' Open for appending at the end of the file without truncating it. Creates a new file if it does not exist. 't' Open in text mode. (default) 'b' Open in binary mode. '+' Open a file for updating (reading and writing) f = open('test.txt') # equivalent to 'r' or 'rt' f = open('test.txt','w') # write in text mode f = open('img.bmp','r+b') # read and write in binary mode Unlike other languages, the character 'a' does not imply the number 97 until it is encoded using ASCII (or other equivalent encodings). Moreover, the default encoding is platform dependent. In windows, it is 'cp1252' but 'utf-8' in Linux. So, we must not also rely on the default encoding or else our code will behave differently in different platforms. How to Convert PAL to NTSC and Vice Versa. Different countries use different analog television encoding standards. If you record your video in the United States using an NTSC camcorder, people in Europe will most likely be unable to watch it on their VCRs. The Mini PAL to NTSC converter is the ideal solution for converting single–format video equipment into a format you can view on your TV. This Bi-directional Digital Multi-System PAL and NTSC converter will take either a PAL or NTSC input and convert it to the other. Hence, when working with files in text mode, it is highly recommended to specify the encoding type. F = open('test.txt',mode = 'r',encoding = 'utf-8') How to close a file Using Python? When we are done with operations to the file, we need to properly close the file. Closing a file will free up the resources that were tied with the file and is done using Python close() method. Python has a garbage collector to clean up unreferenced objects but, we must not rely on it to close the file. F = open('test.txt',encoding = 'utf-8') # perform file operations f.close(). This method is not entirely safe. If an exception occurs when we are performing some operation with the file, the code exits without closing the file. A safer way is to use a block. Try: f = open('test.txt',encoding = 'utf-8') # perform file operations finally: f.close() This way, we are guaranteed that the file is properly closed even if an exception is raised, causing program flow to stop. The best way to do this is using the with statement. This ensures that the file is closed when the block inside with is exited. We don't need to explicitly call the close() method. It is done internally. With open('test.txt',encoding = 'utf-8') as f: # perform file operations How to write to File Using Python? In order to write into a file in Python, we need to open it in write 'w', append 'a' or exclusive creation 'x' mode. We need to be careful with the 'w' mode as it will overwrite into the file if it already exists. All previous data are erased. Writing a string or sequence of bytes (for binary files) is done using write() method. This method returns the number of characters written to the file.
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