Ultimate Python for Fintech Solutions

CHAPTER 1

Getting Started on Python Infrastructure and Building Financial Apps

Introduction

This chapter will introduce the reader to Python Deployment, Anaconda, Python Quant Platform, and other tools such as IPython. The reader will be presented with examples to deploy and execute code to see the results. Python is easy to learn and has a wide range of popular open source frameworks. In fintech, Python is becoming a popular choice as more and more developers are choosing python to develop apps. New technologies like AI, Machine learning, Big data and IOT are being used in Fintech first because most of these tech frameworks are python based.

The many popular tech stacks in Python consist of Django, Django rest framework, Fast API, Flask, Pyramid, Bottle, and others. Most of the fintech popular tech stacks have the JavaScript frameworks as the presentation layer. They are Angular.js, React.js, and Vue.js. The backend is in REST API which can be DRF/Fast API or any other language based REST API.

Structure

In this chapter, we will discuss the following topics:

Python Installation

Anaconda

Python Quant Platform

Tools – Ipython

Figure 1.1: Python Infrastructure Topics

Python Installation

To begin, let us look at the process of installing Python. The setup requires Python 3.9.7, as the code examples will be based on this version of Python. Python software can be downloaded in accordance with the operating system and is available at: https://www.python.org/downloads/release/python-397/.

Figure 1.2: Python Execution Options

Now let us look at all Python execution options as shown in Figure 1.2.

Python Compiler and Executable

After installation, the version of the Python installed can be checked with the following command:

python3 --version

The output, after executing the preceding command, is as follows:

(base) apples-MacBook-Air:code bhagvan.kommadi$ python3 --version

Python 3.9.7

(base) apples-MacBook-Air:code bhagvan.kommadi$

You can test the initial Python program with the following code:

first_program.py

print(python program is working)

def printString():

print(method print string working)

if __name__==__main__:

printString()

The preceding code can be executed using the following command:

python3 first_program.py

The output after executing the preceding command is as follows:

(base) apples-MacBook-Air:code bhagvan.kommadi$ ls

first_program.py

(base) apples-MacBook-Air:code bhagvan.kommadi$ python3 first_program.py

python program is working

method print string working

(base) apples-MacBook-Air:code bhagvan.kommadi$

Figure 1.3: Python Interpreter and Compiler

Figure 1.3 shows how a Python compiler interacts with code and bytecode through an interpreter to a Virtual machine.

JupyterLab

The commands for installing and launching JupyterLab are as follows:

pip3 install jupyterlab

jupyterlab

The output after executing the preceding command is as follows:

(base) apples-MacBook-Air:~ bhagvan.kommadi$ jupyter-lab

[I 2023-07-20 23:23:41.583 ServerApp] jupyterlab | extension was successfully linked.

[I 2023-07-20 23:23:41.584 ServerApp] jupytext | extension was successfully linked.

[I 2023-07-20 23:23:42.348 ServerApp] nbclassic | extension was successfully linked.

The output is shown in Figure 1.4.

Figure 1.4: Jupyter Notebook

A Jupyter notebook can be created by clicking the File Menu.

Figure 1.5: Jupyter Notebook Execution

Figure 1.5 shows the Jupyter Notebook code and the output when the Jupyter Notebook is executed.

Figure 1.6: Jupyter Notebook Naming

Rename the notebook as First Notebook.ipynb.

PipEnv – Python Environment

You can install pipenv using the following command:

Pip3 install --user pipenv

users_api.py

import requests

response = requests.get('https://reqres.in/api/users?page=2')

print (users list json,response.json())

The preceding code can be executed using the following command:

pipenv install requests

The output, after executing the preceding command, is as follows:

(base) apples-MacBook-Air:pipenv_example bhagvan.kommadi$ pipenv install requests

Creating a virtualenv for this project…

The preceding code can be executed using the following command:

python3 users_api.py

The output after executing the preceding command is as follows:

(base) apples-MacBook-Air:pipenv_example bhagvan.kommadi$ pipenv run python3 users_api.py

users list json {'page': 2, 'per_page': 6, 'total': 12, 'total_pages': 2, 'data': [{'id': 7, 'email': '[email protected]', 'first_name': 'Michael', 'last_name': 'Lawson', 'avatar': 'https://reqres.in/img/faces/7-image.jpg'}, {'id': 8, 'email': '[email protected]', 'first_name': 'Lindsay', 'last_name': 'Ferguson', 'avatar': 'https://reqres.in/img/faces/8-image.jpg'}, {'id': 9, 'email': '[email protected]', 'first_name': 'Tobias', 'last_name': 'Funke', 'avatar': 'https://reqres.in/img/faces/9-image.jpg'}, {'id': 10, 'email': '[email protected]', 'first_name': 'Byron', 'last_name': 'Fields', 'avatar': 'https://reqres.in/img/faces/10-image.jpg'}, {'id': 11, 'email': '[email protected]', 'first_name': 'George', 'last_name': 'Edwards', 'avatar': 'https://reqres.in/img/faces/11-image.jpg'}, {'id': 12, 'email': '[email protected]', 'first_name': 'Rachel', 'last_name': 'Howell', 'avatar': 'https://reqres.in/img/faces/12-image.jpg'}], 'support': {'url': 'https://reqres.in/#support-heading', 'text': 'To keep ReqRes free, contributions towards server costs are appreciated!'}}

Figure 1.7: PipEnv Usecase

PipEnv can be used for different projects with different Python environments.

Virtual Env – Python Environment

You can install pipenv using the following command:

python3 -m pip install --user virtualenv

Now you can create a virtual environment using the following command:

python3 -m venv requestsenv

You can activate the requestenv environment by using the following command:

source requestsenv/bin/activate

The output after executing the preceding command is as follows:

(base) apples-MacBook-Air:venv_example bhagvan.kommadi$ python3 -m venv requestsenv

(base) apples-MacBook-Air:venv_example bhagvan.kommadi$ source requestsenv/bin/activate

(requestsenv) (base) apples-MacBook-Air:venv_example bhagvan.kommadi$ which python

/Users/bhagvan.kommadi/OldDesk/orange/Manuscript/chapter1/code/venv_example/requestsenv/bin/python

(requestsenv) (base) apples-MacBook-Air:venv_example bhagvan.kommadi$

Now, let us look at the code that needs to be executed. This is an example of the user’s API, enhanced with logging capability.

users_api_with_logging.py

import requests

import logging

import sys

def getUsers():

response = requests.get('https://reqres.in/api/users?page=2')

#print (users list json,response.json())

logging.getLogger(usersapi).debug(users list,response.json())

if __name__ == __main__:

logging.basicConfig(format=%(levelname)s - %(name)s - %(message)s, level=logging.DEBUG)

logging.getLogger(usersapi).setLevel(logging.DEBUG)

getUsers()

The preceding code can be executed using the following command:

pip3 install requests

python3 users_api_with_logging.py

The output after executing the preceding command is as follows:

(requestsenv) (base) apples-MacBook-Air:venv_example bhagvan.kommadi$ python3 users_api_with_logging.py

DEBUG - urllib3.connectionpool - Starting new HTTPS connection (1): reqres.in:443

DEBUG - urllib3.connectionpool - https://reqres.in:443 GET /api/users?page=2 HTTP/1.1 200 None

DEBUG - usersapi - users list

(requestsenv) (base) apples-MacBook-Air:venv_example bhagvan.kommadi

Figure 1.8: VirtualEnv Use Case

VirtualEnv can be used in multiple projects with different requirements and different Python versions.

Docker – Python Environment

You can first create a docker file, which is outlined as follows:

FROM python:3

WORKDIR /pythonapp

COPY requirements.txt ./

RUN pip3 install --no-cache-dir -r requirements.txt

COPY . .

CMD [ python3, ./first_program.py ]

You can test your first Python program using the following code:

first_program.py

print(python program is working)

def printString():

print(method print string working)

if __name__==__main__:

printString()

The preceding code can be executed using the following command:

docker build -t python-app.

docker run -it --rm --name run_python-app python-app

The output after executing the preceding command is as follows:

(requestsenv) (base) apples-MacBook-Air:docker_example bhagvan.kommadi$ docker build -t python-app.

Sending build context to Docker daemon 11.26kB

Step 1/7 : FROM python:3

---> 608c79ebc6d5

Step 2/7 : WORKDIR /pythonapp

---> Using cache

---> 78a0f6338f9a

Step 3/7 : COPY requirements.txt ./

---> Using cache

---> 28d9db138c8d

Step 4/7 : COPY pythonapp/first_program.py ./

---> 5bbde520d8f9

Step 5/7 : RUN pip3 install --no-cache-dir -r requirements.txt

---> Running in bafc78565b44

WARNING: Running pip as the 'root' user can result in broken permissions and conflicting behavior with the system package manager. It is recommended to use a virtual environment instead: https://pip.pypa.io/warnings/venv

[notice] A new release of pip is available: 23.1.2 -> 23.2.1

[notice] To update, run: pip install --upgrade pip

Removing intermediate container bafc78565b44

---> 973a2458737f

Step 6/7 : COPY . .

---> f7039ce59d4b

Step 7/7 : CMD [ python3, ./first_program.py ]

---> Running in b708d12f6aad

Removing intermediate container b708d12f6aad

---> cfac745dffa6

Successfully built cfac745dffa6

Successfully tagged python-app:latest

(requestsenv) (base) apples-MacBook-Air:docker_example bhagvan.kommadi$ docker run -it --rm --name run_python-app python-app

python program is working

method print string working

(requestsenv) (base) apples-MacBook-Air:docker_example bhagvan.kommadi$

Figure 1.9: Docker Use Case

Docker can be used in projects running on different operating systems. Like Virtual env, it can also handle different requirements.

Anaconda

You can download the Anaconda installer package for your operating system from the provided link : https://www.anaconda.com/download#macos.

Figure 1.10: Anaconda Web Page

Installation can be verified by searching for anaconda in the search bar, as shown in Figure 1.11: