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File, read and write operations.

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So what is a data file file is a logical unit of related information stored on a Nimda location on disk,

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it is used to permanently stored data in a non-volatile memory as example, hard disk.

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We can keep our data in different genotypes.

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So like the numbers, like your tuples, lists, sits, dictionaries and so on.

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But all of them are occupying space in the memory that is REM.

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So when the program will get terminated, when my machine will be shut down, in that case, that data

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will be lost.

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So we are supposed to have some mechanism with the help which we can store our data on to our secondary

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storage.

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That is a nonvolatile storage.

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Let it be hard disk.

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So the best means to do that one is through our data files.

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So filing is a logical unit of related information stored on a location, on a disk, and it is used

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to permanently store data onto a non-volatile memory.

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Here it is, our disk as an example.

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So since random access memory that is REM is volatile, so it cannot be treated for permanent storage

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of data.

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When you want to read from or write to a file, we need to open it at first.

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Then we are we are done.

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And when this one is done, then it needs to be closed so that the resources that are tied with the

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file are getting free.

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So before reading or writing on the data file, at first we are supposed to open the file in the respective

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mode.

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Then what about the operations we are supposed to do and get it done and then we shall close the file

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so that the allocated resources will be declared as a free so.

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Hence, in Python, a file operation takes place in the following sequence that is open a file, read

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or write that is a from the respective operation and then close the file.

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So there are three steps with the help of which the file handling can be done in Python.

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So these are the file python file, Modisane, the first one is are open the file for the reading that

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is a by default if we don't mention it will get opened in the army.

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That is a read what w open the file for writing creates a new file if it does not exist or truncated

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the file if it is existing.

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Next one is open.

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A file for exclusive creation in the file already exists.

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The operation files.

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So then is it XML?

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In case of a mode open a file that is for appending at the end of the file and without truncating it

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creates a new file if it does not exist.

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So that is in case of the file is pre existing and then the pre existing file version will get opened

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and the new content will be appended back.

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If the file is not pre existing then against that, giving them the file get created and that will be

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opened.

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Next one is to open the file in the text won't be open the file in the binary mode and means open a

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file for updating that is reading and writing mode.

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So let us go through some examples here.

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So if one is going to open employee debt here to see we didn't mention any more, so by default this

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armored will be there.

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So equivalent to r r r t, what is out there is a read Dixmoor.

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You can find this one this r t if two is going to open Pigott GPG R plus B.

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So what is the R R stands for this.

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This is my read operation.

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And what is A B B is that is a binary mod that is read and write in the binary mod.

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Next one is the F three that is open.

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There is a text in W mode that is a right in the text mod.

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So in this way we have given some sample codes to show you that how this mould's can be used while opening

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one file.

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Closing a file in Biton, so you see, when we are done with the operations to the file, we need to

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properly close the file and closing is a file.

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Closing a file will free up the resources that were tight with the file as this is done using Python

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closed method.

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So using this closed method, the file will be closed and the allocated memory space which was allocated

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for these files, will be declared as a free space.

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Python has a garbage collector to clean up the unrefuted unreferenced objects, but we must not rely

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on it to close the file.

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So that's why we should close the file ourselves in the coding.

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We should not consider the garbage collector will come and it will make all the unreferenced resources

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to make them free.

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We should not rely on that.

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It is our common practice.

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It is a good practice for the programmers.

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Open the file, do the operations and close it.

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So here we are having some examples.

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So if it is going to open employed or that encoding is a goal to UTF eight and then perform some operations

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file operations, and then if that close to close the file so that they are allocated, resources will

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be declared as free.

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So in this particular video, we have discussed that how to perform the region.

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Right.

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Operations on file in case of Python.

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That's what watching this video.