<SYSTEM_TASK:>
Given the following text description, write Python code to implement the functionality described below step by step
<END_TASK>
<USER_TASK:>
Description:
 <p><font size="6"><b>Jupyter notebook INTRODUCTION </b></font></p>
© 2021, Joris Van den Bossche and Stijn Van Hoey  (&#106;&#111;&#114;&#105;&#115;&#118;&#97;&#110;&#100;&#101;&#110;&#98;&#111;&#115;&#115;&#99;&#104;&#101;&#64;&#103;&#109;&#97;&#105;&#108;&#46;&#99;&#111;&#109;, &#115;&#116;&#105;&#106;&#110;&#118;&#97;&#110;&#104;&#111;&#101;&#121;&#64;&#103;&#109;&#97;&#105;&#108;&#46;&#99;&#111;&#109;). Licensed under CC BY 4.0 Creative Commons
Step1:  <big><center>To run a cell
Step2:  Writing code is what you will do most during this course!
Markdown
Text cells, using Markdown syntax. With the syntax, you can make text bold or italic, amongst many other things...
list
with
items
Link to interesting resources or images
Step3:  Help
Step4:  <div class="alert alert-success">
    <b>EXERCISE 1</b>
Step5:  edit mode to command mode
edit mode means you're editing a cell, i.e. with your cursor inside a cell to type content
command mode means you're NOT editing(!), i.e. NOT with your cursor inside a cell to type content
To start editing, click inside a cell or 
<img src="../img/enterbutton.png" alt="Key enter" style="width
Step6:  %%timeit
Step7:  %whos
Step8:  %lsmagic
Step9:  Let's get started!
<ASSISTANT_TASK:>
Python Code:
from IPython.display import Image
Image(url='http://python.org/images/python-logo.gif')
Explanation: <p><font size="6"><b>Jupyter notebook INTRODUCTION </b></font></p>
© 2021, Joris Van den Bossche and Stijn Van Hoey  (&#106;&#111;&#114;&#105;&#115;&#118;&#97;&#110;&#100;&#101;&#110;&#98;&#111;&#115;&#115;&#99;&#104;&#101;&#64;&#103;&#109;&#97;&#105;&#108;&#46;&#99;&#111;&#109;, &#115;&#116;&#105;&#106;&#110;&#118;&#97;&#110;&#104;&#111;&#101;&#121;&#64;&#103;&#109;&#97;&#105;&#108;&#46;&#99;&#111;&#109;). Licensed under CC BY 4.0 Creative Commons
End of explanation
# Code cell, then we are using python
print('Hello DS')
DS = 10
print(DS + 5) # Yes, we advise to use Python 3 (!)
Explanation: <big><center>To run a cell: push the start triangle in the menu or type SHIFT + ENTER/RETURN
Notebook cell types
We will work in Jupyter notebooks during this course. A notebook is a collection of cells, that can contain different content:
Code
End of explanation
import os
os.mkdir
my_very_long_variable_name = 3
Explanation: Writing code is what you will do most during this course!
Markdown
Text cells, using Markdown syntax. With the syntax, you can make text bold or italic, amongst many other things...
list
with
items
Link to interesting resources or images: 
Blockquotes if you like them
This line is part of the same blockquote.
Mathematical formulas can also be incorporated (LaTeX it is...)
$$\frac{dBZV}{dt}=BZV_{in} - k_1 .BZV$$
$$\frac{dOZ}{dt}=k_2 .(OZ_{sat}-OZ) - k_1 .BZV$$
Or tables:
course | points
 --- | --- 
 Math | 8
 Chemistry | 4
or tables with Latex..
Symbool | verklaring
 --- | --- 
 $$BZV_{(t=0)}$$          | initiële biochemische zuurstofvraag (7.33 mg.l-1)
 $$OZ_{(t=0)}$$     | initiële opgeloste zuurstof (8.5 mg.l-1)
 $$BZV_{in}$$         | input BZV(1 mg.l-1.min-1)
 $$OZ_{sat}$$         | saturatieconcentratie opgeloste zuurstof (11 mg.l-1)
 $$k_1$$              | bacteriële degradatiesnelheid (0.3 min-1)
 $$k_2$$              | reäeratieconstante (0.4 min-1)
Code can also be incorporated, but than just to illustrate:
python
BOT = 12
print(BOT)
See also: https://github.com/adam-p/markdown-here/wiki/Markdown-Cheatsheet
HTML
You can also use HTML commands, just check this cell:
<h3> html-adapted titel with &#60;h3&#62; </h3>
<p></p>
<b> Bold text &#60;b&#62; </b> of <i>or italic &#60;i&#62; </i>
Headings of different sizes: section
subsection
subsubsection
Raw Text
Notebook handling ESSENTIALS
Completion: TAB
The TAB button is essential: It provides you all possible actions you can do after loading in a library AND it is used for automatic autocompletion:
End of explanation
round(3.2)
import os
os.mkdir
# An alternative is to put a question mark behind the command
os.mkdir?
Explanation: Help: SHIFT + TAB
The  SHIFT-TAB combination is ultra essential to get information/help about the current operation
End of explanation
import glob
glob.glob??
Explanation: <div class="alert alert-success">
    <b>EXERCISE 1</b>: What happens if you put two question marks behind the command?
</div>
End of explanation
%psearch os.*dir
Explanation: edit mode to command mode
edit mode means you're editing a cell, i.e. with your cursor inside a cell to type content
command mode means you're NOT editing(!), i.e. NOT with your cursor inside a cell to type content
To start editing, click inside a cell or 
<img src="../img/enterbutton.png" alt="Key enter" style="width:150px">
To stop editing,
<img src="../img/keyescape.png" alt="Key A" style="width:150px">
new cell A-bove
<img src="../img/keya.png" alt="Key A" style="width:150px">
Create a new cell above with the key A... when in command mode
new cell B-elow
<img src="../img/keyb.png" alt="Key B" style="width:150px">
Create a new cell below with the key B... when in command mode
CTRL + SHIFT + C
Just do it!
Trouble...
<div class="alert alert-danger">
    <b>NOTE</b>: When you're stuck, or things do crash: 
    <ul>
    <li> first try <code>Kernel</code> > <code>Interrupt</code> -> your cell should stop running
    <li> if no succes -> <code>Kernel</code> > <code>Restart</code> -> restart your notebook
    </ul>
</div>
Stackoverflow is really, really, really nice!
http://stackoverflow.com/questions/tagged/python
Google search is with you!
<big><center>REMEMBER: To run a cell: <strike>push the start triangle in the menu or</strike> type SHIFT + ENTER
some MAGIC...
%psearch
End of explanation
%%timeit
mylist = range(1000)
for i in mylist:
    i = i**2
import numpy as np
%%timeit
np.arange(1000)**2
Explanation: %%timeit
End of explanation
%whos
Explanation: %whos
End of explanation
%lsmagic
Explanation: %lsmagic
End of explanation
from IPython.display import FileLink, FileLinks
FileLinks('.', recursive=False)
Explanation: Let's get started!
End of explanation
<END_TASK>