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This assignment is a programming exercise and you will need to create file called assignment$2.$py

Note that there are strict requirements how class and methods should be named. If you fail to follow the requirement, your work will not be graded. Each task is worth $1$ point.

You don't need to implement validation of the input parameters, we will always supply legitimate values in our testing scripts.

Make sure you implement each requested function as a class method! Unless it is explicitly asking for a static method, you must include self as a first special argument. For example, if asking to create a method foobar taking two arguments, you should write something like

class Assignment$2$:

def foobar$($self$,$ first$\_$argument, second$\_$argument$)$:

# body of the method

Task $1($Constructor$)$

Implement a constructor that accepts one parameter: year $($type int$).$ This parameter should initialize the similarly named class instance variable $($hint: these would start with self.$)$

Task $2($Age$)$

Implement method named tellAge. This method should accept a single argument: currentYear $($type int$).$

The result of this method should be printing on the standard output the following line:

Your age is XXXX

Where XXXX is calculated birth year, based on the supplied currentYear argument and year from the class instance variable.

Task $3($List$)$

Write a method named listAnniversaries that doesn't accepts arguments.

This method should return a list $($note$,$ unlike task $2,$ not to print, but return a list!$)$ containing all $10-$year anniversaries, assuming today is year $2022.$ For example, when running the following code

a $=$ Assignment$2(2000)$

ret $=$ a$.$listAnniversaries$()$

print$($ret$)$

The output should be $[10,20].$

And when running the following:

a $=$ Assignment$2(1991)$

ret $=$ a$.$listAnniversaries$()$

print$($ret$)$

The output should be $[10,20,30].$

Task $4($String Manipulation$)$

Write a method named modifyYear with the following specification:

Input parameters:

variable named n$,$ type int: number to adjust list size

Return value should be a string, containing:

n times the first two characters in the text representation of the year $($e$.$g$.,$ if year $2000$ and n$=5,$ then this part should be $"2020202020")$

odd positioned characters of text representation of year multiplied by n $($if year is $2000$ and n$=5,$ then text representation is $"10000"$ and you seelct odd characters, which is $"100"$; if year $1782$ and n$=3,$ then text representation is $"5346"$ and you select $"54".$

For example,

a $=$ Assignment$2(1782)$

ret $=$ a$.$modifyYear$(3)$

print$($ret$)$

should print $17171754.$

Task $5($Loop and Conditional statements$)$

Write a static method named checkGoodString with the following specification. Note that static methods don't have self but must be annotated with @staticmethod.

Input parameters:

variable named string, type str

Return Value:

type bool: True if string has the following requirements

Is at least $9$ characters long

Starts with lower case letter a$-$z

Contains only one number $0-9$

For example,

ret $=$ Assignment$2.$checkGoodString$("$f$1$obar$0$more"$)$

print$($ret$)$

ret $=$ Assignment$2.$checkGoodString$("$foobar$0$more"$)$

print$($ret$)$

should print

False

True

Task $6($Socket$)$

Write a static method named connectTcp that will create TCP IPv$4$ socket $($AF$\_$INET, SOCK$\_$STREAM$),$ connect to the specified host$/$port$,$ closes the connection, and returns True if the connection was established correctly.

Input parameters:

variable named host: type str

variable named port: type int

Return value

type bool: True if TCP connection successfully established, otherwise False

You can test this method with any Internet service, for example:

retval $=$ Assignment$2.$connectTcp$("$www$.$google.com", $80)$

if retval:

print$("$Connection established correctly"$)$

else:

print$("$Some error"$)$

Note that Python $3$ by default will throw an exception if you trying to connect and connection cannot be established. You will need to handle this case to return False as required by this task.