diff --git a/.gitignore b/.gitignore
index 5d0cce2..0a7201e 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1,162 @@
-notes\ cours\ python
+
+# Created by https://www.gitignore.io/api/vim,python,visualstudiocode
+# Edit at https://www.gitignore.io/?templates=vim,python,visualstudiocode
+
+### Python ###
+# Byte-compiled / optimized / DLL files
+__pycache__/
+*.py[cod]
+*$py.class
+
+# C extensions
+*.so
+
+# Distribution / packaging
+.Python
+build/
+develop-eggs/
+dist/
+downloads/
+eggs/
+.eggs/
+lib/
+lib64/
+parts/
+sdist/
+var/
+wheels/
+pip-wheel-metadata/
+share/python-wheels/
+*.egg-info/
+.installed.cfg
+*.egg
+MANIFEST
+
+# PyInstaller
+#  Usually these files are written by a python script from a template
+#  before PyInstaller builds the exe, so as to inject date/other infos into it.
+*.manifest
+*.spec
+
+# Installer logs
+pip-log.txt
+pip-delete-this-directory.txt
+
+# Unit test / coverage reports
+htmlcov/
+.tox/
+.nox/
+.coverage
+.coverage.*
+.cache
+nosetests.xml
+coverage.xml
+*.cover
+.hypothesis/
+.pytest_cache/
+
+# Translations
+*.mo
+*.pot
+
+# Django stuff:
+*.log
+local_settings.py
+db.sqlite3
+db.sqlite3-journal
+
+# Flask stuff:
+instance/
+.webassets-cache
+
+# Scrapy stuff:
+.scrapy
+
+# Sphinx documentation
+docs/_build/
+
+# PyBuilder
+target/
+
+# Jupyter Notebook
+.ipynb_checkpoints
+
+# IPython
+profile_default/
+ipython_config.py
+
+# pyenv
+.python-version
+
+# pipenv
+#   According to pypa/pipenv#598, it is recommended to include Pipfile.lock in version control.
+#   However, in case of collaboration, if having platform-specific dependencies or dependencies
+#   having no cross-platform support, pipenv may install dependencies that don't work, or not
+#   install all needed dependencies.
+#Pipfile.lock
+
+# celery beat schedule file
+celerybeat-schedule
+
+# SageMath parsed files
+*.sage.py
+
+# Environments
+.env
+.venv
+env/
+venv/
+ENV/
+env.bak/
+venv.bak/
+
+# Spyder project settings
+.spyderproject
+.spyproject
+
+# Rope project settings
+.ropeproject
+
+# mkdocs documentation
+/site
+
+# mypy
+.mypy_cache/
+.dmypy.json
+dmypy.json
+
+# Pyre type checker
+.pyre/
+
+### Vim ###
+# Swap
+[._]*.s[a-v][a-z]
+[._]*.sw[a-p]
+[._]s[a-rt-v][a-z]
+[._]ss[a-gi-z]
+[._]sw[a-p]
+
+# Session
+Session.vim
+Sessionx.vim
+
+# Temporary
+.netrwhist
+*~
+# Auto-generated tag files
+tags
+# Persistent undo
+[._]*.un~
+
+### VisualStudioCode ###
+.vscode/*
+!.vscode/settings.json
+!.vscode/tasks.json
+!.vscode/launch.json
+!.vscode/extensions.json
+
+### VisualStudioCode Patch ###
+# Ignore all local history of files
+.history
+
+# End of https://www.gitignore.io/api/vim,python,visualstudiocode
diff --git a/ML/udemy/Data.csv b/ML/udemy/Data.csv
new file mode 100755
index 0000000..564b65b
--- /dev/null
+++ b/ML/udemy/Data.csv
@@ -0,0 +1,11 @@
+Country,Age,Salary,Purchased
+France,44,72000,No
+Spain,27,48000,Yes
+Germany,30,54000,No
+Spain,38,61000,No
+Germany,40,,Yes
+France,35,58000,Yes
+Spain,,52000,No
+France,48,79000,Yes
+Germany,50,83000,No
+France,37,67000,Yes
\ No newline at end of file
diff --git a/ML/udemy/fill_empty_data.py b/ML/udemy/fill_empty_data.py
new file mode 100644
index 0000000..06c6970
--- /dev/null
+++ b/ML/udemy/fill_empty_data.py
@@ -0,0 +1,21 @@
+# Data preprocessing
+import numpy as np
+import matplotlib.pyplot as plt
+import pandas as pd 
+
+# Importing the dataset
+dataset = pd.read_csv('Data.csv')
+# Create the matrix of features (independant variables)
+# [:, = lines -- all of them
+# :-1] = colums -- all of them unless the last one 
+# X = (Country, Age, Salary)
+X = dataset.iloc[:, :-1].values
+# Create vector of linked variables
+# [:, 3] = all values of the 3rd column
+# Y = (Purchased)
+X = dataset.iloc[:, 3].values
+
+# Taking care of the missing data
+from sklearn.model_selection import train_test_split
+
+imputer = Imputer(missing_values = 'NaN', strategy = 'mean', axis = 0)
diff --git a/edx-python/w1/problem3-w1.py b/edx-python/w1/problem3-w1.py
index 7fa0217..d6046a4 100644
--- a/edx-python/w1/problem3-w1.py
+++ b/edx-python/w1/problem3-w1.py
@@ -4,4 +4,8 @@ alphabet = string.ascii_lowercase
 
 s = 'azcbobobegghakl'
 count = 0
+print(alphabet)
 
+for i in s:
+    print i
+    print index(i)