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How to decode Tag-Length-Value Quickly

Basically, in TLV, the format is Tag, Length, and Value. In the list of protocols, TLV is one of the types. Transmitting the data depends on the protocol you used. However, many financial transactions still follow the TLV format. According to IBM, TLV data is three parts. The tag tells what type of data it is. The length field has a length of the value. The Value field has actual value.

Structure of TLV.TLV comprises three field values.  TagLengthValueEMV formulated different tags. They have their own meanings. Usually, the Tag and Length together takes 1 to 4 bytes.
The Best example for TLV.In the below example, you can find the sample TAG, LENGTH, and VALUE fields.

[Tag][Value Length][Value] (ex. "9F4005F000F0A001")
where

Tag Name = 9F40

Value Length (in bytes) = 05 
Value (Hex representation of bytes. Example, "F0" – 1-byte) = F000F0A001

In the above message, tag 9F40 has some meaning designed by EMV company. Here you can find a list of EMV Tags.
How to read the TLVTag: 1…
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How to use Python Interactive Shell in an easy way

Python Interactive Shell
[Python Interactive Shell]

It's like this: Python leads a double life. It's an interpreter for scripts that you can run from the command line or run like applications, by double-clicking the scripts. 

What is Interactive Shell

But it's also an interactive shell that can evaluate arbitrary statements and expressions. This is extremely useful for debugging, quick hacking, and testing.

I even know some people who use the Python interactive shell in lieu of a calculator! 

Launch the Python interactive shell in whatever way works on your platform, and let's dive in with the steps shown here:

First Steps in the Interactive Shell
>>> 1 + 1 ❶
2
>>> print 'hello world' ❷
hello world
>>> x = 1 ❸
>>> y = 2
>>> x + y
3
❶ The Python interactive shell can evaluate arbitrary Python expressions, including any basic arithmetic expression.
❷ The interactive shell can execute arbitrary Python statements, including the print statement. 
❸ You can also assign values to variables, and the values will be remembered as long as the shell is
open (but not any longer than that).

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