First, let’s talk about Reference Types and Value Types. I think people don’t really understand the differences and benefits of both. They usually say reference types store content on the heap and value types store content on the stack, which is wrong.

Let’s discuss the real differences:

• A value type: its value is an entire structure. The value of a reference type is a reference to an object. – A structure in memory: value types contain only the data you indicated. Reference types also contain two system fields. The first one stores 'SyncBlockIndex', the second one stores the information about a type, including the information about a Virtual Methods Table (VMT).
• Reference types can have methods that are overridden when inherited. Value types cannot be inherited.
• You should allocate space on the heap for an instance of a reference type. A value type can be allocated on the stack, or it becomes the part of a reference type. This sufficiently increases the performance of some algorithms.

However, there are common features:

• Both subclasses can inherit the object type and become its representatives.

Let’s look closer at each feature.

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Solution overview

Introduction

For the last five years, there have virtually been almost no global-scale application-layer attacks.

During this period, the industry has learned how to cope with the high bandwidth network layer attacks, including amplification-based ones. It does not mean that botnets are now harmless.

End of June 2021, Qrator Labs started to see signs of a new assaulting force on the Internet – a botnet of a new kind. That is a joint research we conducted together with Yandex to elaborate on the specifics of the DDoS attacks enabler emerging in almost real-time.

At the beginning of the year 2021, Qrator Labs is celebrating its 10 year anniversary. On January 19 our company marks the official passing of a formal 10 years longevity mark, entering its second decade of existence. 

Everything started a little bit earlier - when at the age of 10 Alex saw the Robotron K 1820 - in 2008, when Alexander Lyamin - the founder and CEO of Qrator Labs, approached the Moscow State University superiors, where he worked as a NOC engineer at the time, with an idea of a DDoS-attack mitigation research project. The MSU's network was one of the largest in the country and, as we know now, it was the best place to hatch a future technology.

That time MSU administration agreed, and Mr Lyamin took his own hardware to the university, simultaneously gathering a team. In two years, by summer 2010, the project turned out to be that successful. It courted the DDoS attack of a bandwidth exceeding the MSU's upstream bandwidth capability. And on June 22 MSU superiors gave Mr Lyamin a choice - to shut down or find money to incorporate.

Alexander Lyamin chose to incorporate with his own means, which effectively meant that the needed infrastructure must be built from scratch. The initial design should be distributed instead of concentrated within one network, which resources were not enough for this specific task. And by September 1, 2010, those first server sites were ready and running.

tl;dr

pip install fast-enum

What are enums

# /path/to/package/static.py:
INITIAL = 0
PROCESSING = 1
PROCESSED = 2
DECLINED = 3
RETURNED = 4
...

class MyModelStates:
  INITIAL = 0
  PROCESSING = 1
  PROCESSED = 2
  DECLINED = 3
  RETURNED = 4