Given the following dictionary:

$\{\text{'}45698\text{'}$: 'John Smith',$\text{'}54600\text{'}$:'Mark Sebastian',$\text{'}10100\text{'}$: 'Ruben Quin'$\}$

Where: key represents the customer id and value the customer's name.

Write a program that iterates through the dictionary, print the customer id and then search and print if the customer's name has the letter $\text{'}i\text{'}$ followed by two other characters. The output will look like this:

$$ Searching customer id: $45698$

Substring is ith

$$ Searching customer id: $54600$

Substring is ian

$$ Searching customer id: $10100$

Not found

$[$Finished in $49ms]$

Please explain and use ten lines of code