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Given the following text description, write Python code to implement the functionality described below step by step
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Description:
 Git
Step1:  And how you will edit text files (it will often ask you to edit messages and other information, and thus wants to know how you like to edit your files)
Step2:  Stage 0
Step3:  Then paste the key into your Gitlab or github account
Stage 1
Step4:  We are going to create a test repo for git to play
git init
Step5:  Let's look at what git did
Step6:  The folder is empty now.
Lets create a new repo in the folder.
Step7:  Now you can see that there is a hidden folder .git (notice the dot that marks it as a hidden folder), which is the GIT repo
Step8:  Now let's edit our first file in the test directory with a text editor... I'm doing it programatically here for automation purposes, but you'd normally be editing by hand
Step9:  ls lists the contents of the current working directory
Step10:  git add
Step11:  We can now ask git about what happened with status
Step12:  git commit
Step13:  In the commit above, we  used the -m flag to specify a message at the command line.  If we don't do that, git will open the editor we specified in our configuration above and require that we enter a message.  By default, git refuses to record changes that don't have a message to go along with them (though you can obviously 'cheat' by using an empty or meaningless string
Step14:  git diff
Step15:  And now we can ask git what is different
Step16:  The cycle of git virtue
Step17:  git log revisited
First, let's see what the log shows us now
Step18:  Sometimes it's handy to see a very summarized version of the log
Step19:  Git supports aliases
Step20:  git mv and rm
Step21:  Note that these changes must be committed too, to become permanent!  In git's world, until something hasn't been committed, it isn't permanently recorded anywhere.
Step22:  And git rm works in a similar fashion removing the file from your repo.
Local user, branching
What is a branch?  A branch is a label for the state of a GIT repositories. It makes it easy to develop features and go back and forth between the original master and the copy feature branch version of the files inside the GIT repo
Credit
Step23:  We are now going to try two different routes of development
Step24:  As you can see there are no emjois file in master yet
Step25:  Using remotes as a single user
We are now going to introduce the concept of a remote repository
Step26:  Since the above cell didn't produce any output after the git remote -v call, it means we have no remote repositories configured.  We will now proceed to do so.  Once logged into Github or Gitlab, go to the new repository page and make a repository called test.  Do not check the box that says Initialize this repository with a README, since we already have an existing repository here.  That option is useful when you're starting first at Github and don't have a repo made already on a local computer.
We can now follow the instructions from the next page
Step27:  And now we go back to the master branch, where we change the same file
Step28:  So now let's see what happens if we try to merge the trouble branch into master
Step29:  Let's see what git has put into our file
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Python Code:
!git config --global user.name "joaquin" # replace joaquin by your name
!git config --global user.email "user@gmail.com" # replace j by your email
Explanation: Git: Version control intro
“Revision control, also known as version control, source control
or software configuration management (SCM), is the
management of changes to documents, programs, and other
information stored as computer files.” -- Wikipedia
Reproducibility?
Tracking and recreating every step of your work
In the software world: it's called Version Control!
What do (good) version control tools give you?
Peace of mind (backups)
Freedom (exploratory branching)
Collaboration (synchronization)
Git is an enabling technology: Use version control for everything
Write documents (never get paper_v5_john_jane_final_oct22_really_final.tex by email again!)
Write code
Backup your computer configuration
This tutorial is structured in the following way: we will begin with a brief overview of key concepts you need to understand in order for git to really make sense.  We will then dive into hands-on work: after a brief interlude into necessary configuration we will discuss 5 "stages of git" with scenarios of increasing sophistication and complexity, introducing the necessary commands for each stage:
Local, single-user, linear workflow
Single local user, branching
Using remotes as a single user
Remotes for collaborating in a small team
distributed collaboration with large teams with GitHub/GitLab
In reality, this tutorial only covers stages 1-4, since for #5 there are many software develoment-oriented tutorials and documents of very high quality online.  But most scientists start working alone with a few files or with a small team, so I feel it's important to build first the key concepts and practices based on problems scientists encounter in their everyday life and without the jargon of the software world.  Once you've become familiar with 1-4, the excellent tutorials that exist about collaborating on github on open-source projects should make sense.
Very high level picture: an overview of key concepts
The commit: a snapshot of work at a point in time Every ball in this diagram represents a commit of all the files in a code repository, that we can go later in time, compare it with. We can also add labels/tags to this commits in case we want to develop new features.
Credit: Gitflow Atlassian
And this is pretty much the essence of Git!
First things first: git must be configured before first use
The minimal amount of configuration for git to work without pestering you is to tell it who you are:
Exercise
The preceding ! marks that this code  will execute in the terminal interpreter instead of in python
Lets tell Git who you are.
End of explanation
# Put here your preferred editor. If this is not set, git will honor the $EDITOR environment variable
# On Windows: Notepad works, Notepad++, sublime or atom
# On mac/linux: vim, sublime or atom as a basic option
!git config --global core.editor nvim  # my lightweight neovim editor
# And while we're at it, we also turn on the use of color, which is very useful
!git config --global color.ui "auto"
Explanation: And how you will edit text files (it will often ask you to edit messages and other information, and thus wants to know how you like to edit your files):
End of explanation
#! ssh-keygen -f ~/.ssh/id_rsa -t rsa -N ''
#! less ~/.ssh/id_rsa.pub
Explanation: Stage 0: Configure GIT
Github is offers in its help pages instructions on how to configure the credentials helper for Mac OSX and Windows.
First we are going to create an SSH key that you can upload to Gitlab to recognize you. The key has a private part id_rsa that you should keep secret, and a public part id_rsa.pub that can upload it to Gitlab so gitlab knows it's you.
Uncomment the following 2 lines, and make sure you run them only once, so you generate the key only one time.
End of explanation
!git
Explanation: Then paste the key into your Gitlab or github account
Stage 1: Local, single-user, linear workflow
Simply type git to see a full list of all the 'core' commands.  We'll now go through most of these via small practical exercises:
End of explanation
! mkdir playground_repo
cd playground_repo
Explanation: We are going to create a test repo for git to play
git init: create an empty repository
first we create a folder called playground_repo
End of explanation
ls -la
Explanation: Let's look at what git did:
End of explanation
! git init
ls -la
Explanation: The folder is empty now.
Lets create a new repo in the folder.
End of explanation
ls -l .git
Explanation: Now you can see that there is a hidden folder .git (notice the dot that marks it as a hidden folder), which is the GIT repo
End of explanation
!echo "My first bit of text in the repo" > README.md
Explanation: Now let's edit our first file in the test directory with a text editor... I'm doing it programatically here for automation purposes, but you'd normally be editing by hand
End of explanation
ls
Explanation: ls lists the contents of the current working directory
End of explanation
!git add README.md
Explanation: git add: tell git about this new file
End of explanation
!git status
Explanation: We can now ask git about what happened with status:
End of explanation
!git commit -a -m "First commit"
Explanation: git commit: permanently record our changes in git's database
For now, we are always going to call git commit either with the -a option or with specific filenames (git commit file1 file2...).  This delays the discussion of an aspect of git called the index (often referred to also as the 'staging area') that we will cover later.  Most everyday work in regular scientific practice doesn't require understanding the extra moving parts that the index involves, so on a first round we'll bypass it.  Later on we will discuss how to use it to achieve more fine-grained control of what and how git records our actions.
End of explanation
!git log
Explanation: In the commit above, we  used the -m flag to specify a message at the command line.  If we don't do that, git will open the editor we specified in our configuration above and require that we enter a message.  By default, git refuses to record changes that don't have a message to go along with them (though you can obviously 'cheat' by using an empty or meaningless string: git only tries to facilitate best practices, it's not your nanny).
git log: what has been committed so far
End of explanation
!echo "And now we add a second line..." >> README.md
Explanation: git diff: what have I changed?
Let's do a little bit more work... Again, in practice you'll be editing the files by hand, here we do it via shell commands for the sake of automation (and therefore the reproducibility of this tutorial!)
End of explanation
!git diff
Explanation: And now we can ask git what is different:
End of explanation
!git commit -a -m "added second line."
Explanation: The cycle of git virtue: work, commit, work, commit, ...
End of explanation
!git log
Explanation: git log revisited
First, let's see what the log shows us now:
End of explanation
!git log --oneline --topo-order --graph
Explanation: Sometimes it's handy to see a very summarized version of the log:
End of explanation
# We create our alias (this saves it in git's permanent configuration file):
!git config --global alias.slog "log --oneline --topo-order --graph"
# And now we can use it
!git slog
Explanation: Git supports aliases: new names given to command combinations. Let's make this handy shortlog an alias, so we only have to type git slog and see this compact log:
End of explanation
!git mv README.md README.markdown
!git status
Explanation: git mv and rm: moving and removing files
While git add is used to add fils to the list git tracks, we must also tell it if we want their  names to change or for it to stop tracking them.  In familiar Unix fashion, the mv and rm git commands do precisely this:
End of explanation
!git commit -a -m "I like this new name better"
!echo "Let's look at the log again:"
!git slog
Explanation: Note that these changes must be committed too, to become permanent!  In git's world, until something hasn't been committed, it isn't permanently recorded anywhere.
End of explanation
!git status
!ls
Explanation: And git rm works in a similar fashion removing the file from your repo.
Local user, branching
What is a branch?  A branch is a label for the state of a GIT repositories. It makes it easy to develop features and go back and forth between the original master and the copy feature branch version of the files inside the GIT repo
Credit: Gitflow Atlassian
There can be multiple branches alive at any point in time; the working directory is the state of a special pointer called HEAD.  In this example there are two branches, master and develop:
Once new commits are made on a branch, HEAD and the branch label move with the new commits:
This allows the history of both branches to diverge:
But based on this graph structure, git can compute the necessary information to merge the divergent branches back and continue with a unified line of development:
Let's now illustrate all of this with a concrete example.
End of explanation
!git branch emojis
!git checkout emojis
!echo "Some emojis :smile:, :horse:, :cat:" > emojis.md
!git add emojis.md
!git commit -a -m "Adding some emojis"
!git slog
!git checkout master
!git slog
!ls
Explanation: We are now going to try two different routes of development: on the master branch we will add one file and on the emojis branch, which we will create, we will add a different one.  We will then merge the emojis branch into master.
End of explanation
!echo "All the while, more work goes on in master..." >> README.markdown
!git commit -a -m "The mainline keeps moving"
!git slog
ls
!git merge emojis -m 'merge emojis'
!git slog
Explanation: As you can see there are no emjois file in master yet
End of explanation
!git remote -v
Explanation: Using remotes as a single user
We are now going to introduce the concept of a remote repository: a pointer to another copy of the repository that lives on a different location.  This can be simply a different path on the filesystem or a server on the internet.
For this discussion, we'll be using remotes hosted on the GitHub.com service, but you can equally use other services like Gitlab
Let's see if we have any remote repositories here:
End of explanation
!git branch trouble
!git checkout trouble
!echo "This is going to be a problem..." >> README.markdown
!git commit -a -m "Adding a file for trouble"
Explanation: Since the above cell didn't produce any output after the git remote -v call, it means we have no remote repositories configured.  We will now proceed to do so.  Once logged into Github or Gitlab, go to the new repository page and make a repository called test.  Do not check the box that says Initialize this repository with a README, since we already have an existing repository here.  That option is useful when you're starting first at Github and don't have a repo made already on a local computer.
We can now follow the instructions from the next page:
An important aside: conflict management
While git is very good at merging, if two different branches modify the same file in the same location, it simply can't decide which change should prevail.  At that point, human intervention is necessary to make the decision.  Git will help you by marking the location in the file that has a problem, but it's up to you to resolve the conflict.  Let's see how that works by intentionally creating a conflict.
We start by creating a branch and making a change to our experiment file:
End of explanation
!git checkout master
!echo "At the same time master keeps working on same line will cause a MERGE CONFLICT ..." >> README.markdown
!git commit -a -m "Keep working on the experiment"
Explanation: And now we go back to the master branch, where we change the same file:
End of explanation
!git checkout master
!git merge trouble
Explanation: So now let's see what happens if we try to merge the trouble branch into master:
End of explanation
#!git commit -a -m "Completed merge of trouble, fixing conflicts along the way"
#!git slog
Explanation: Let's see what git has put into our file:
At this point, we go into the file with a text editor, decide which changes to keep, and make a new commit that records our decision.  I've now made the edits, in this case I decided that both pieces of text were useful, but integrated them with some changes:
Let's then make our new commit:
End of explanation
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