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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:
 Motion Functions
In this notebook you will learn how use Python functions for moving the robot in your programs.
First, the initialization step needs to be executed.
Step1:  Functions
There are three functions for controlling the motion of the robot
Step2:  You can also copy and paste the functions several times with different values for a composition of motions
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Python Code:
# click on this cell and press Shift+Enter
import packages.initialization
import pioneer3dx as p3dx
p3dx.init()
Explanation: Motion Functions
In this notebook you will learn how use Python functions for moving the robot in your programs.
First, the initialization step needs to be executed.
End of explanation
# Move forward
p3dx.move(2.5,2.5)
p3dx.sleep(1)
p3dx.stop()
# Move backward
p3dx.move(-2.5,-2.5)
p3dx.sleep(1)
p3dx.stop()
# Turn left
p3dx.move(-2.5,2.5)
p3dx.sleep(1)
p3dx.stop()
# Turn Right
p3dx.move(2.5,-2.5)
p3dx.sleep(1)
p3dx.stop()
Explanation: Functions
There are three functions for controlling the motion of the robot:
* p3dx.move(ls,rs)
* p3dx.stop()
* p3dx.sleep(t)
The main motion function is:
python
p3dx.move(ls, rs)
where
ls : left wheel speed (rad/s)
   rs : right wheel speed (rad/s)
The function sets the speeds of the wheels, and the robot moves until blocked by an obstacle, or a new speed is set, or it is stopped with the function: 
python
p3dx.stop()
For controlling the amount of time that the robot moves, there is the function:
python
p3dx.sleep(t)
where t is the number of seconds. During that pause, the program sleeps but the robot keeps moving with the last speed set.
Example
Use the code below for moving the robot. Feel free to explore with different speed and time values.
End of explanation
# Your own wonderful motion sequence
Explanation: You can also copy and paste the functions several times with different values for a composition of motions:
End of explanation
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