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Hi, everyone.

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In today's example, we're going to transform this list of file names into this.

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So that's the output of the program.

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So let's suppose we had some files and we got their file names using some other functions, which we'll

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learn later on in the course.

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And those functions created a list.

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And then you want to first change these strings into the new names.

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And for that you use a list comprehension, which we will do now.

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And then maybe later on, you reassign those strings to the existing files on disk.

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So today we're simply going to work on transforming the strings.

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So we got these names, the existing names of the files.

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Now we want to transform them.

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So when you want to transform a list, what you think is a list comprehension.

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So let's write the list comprehension.

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We will replace we will overwrite the existing variable with the new list, which is constructed by

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the list comprehension.

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So what do we want to do to the file names?

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You see, this is one dot, doc, and we want to transform it to one dash doc plus dot text.

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So how do we replace the dots with a dash?

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Well, using that replace.

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So file name is a string.

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In the first iteration, it represents the first string.

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So that expects a string, which means the character you want to replace.

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And another string, the character that you want the existing character to be replaced with.

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So the new list is going to contain.

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The string with that character replaced, plus another string, which is the text.

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So that will construct a new string.

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Because it is possible to.

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Concatenate two strings so you get.

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Hey there.

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That's what we're doing there.

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For file name in file names, print, file names, run.

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And here is the result.

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So that's the final code.

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That is the syntax of the list comprehension.

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So it always starts with the new version of each item.

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So the new version of each item is this.

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The character replaced.

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Plus this added to the.

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New string.

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And you do that for each file name in the file names list.

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So thanks for following.