Insider Trading Tutorial - 4

insider-trading-tutorial-4.py

import xml.etree.ElementTree as ET
import re
import time

# Download the XML version of the filing. If it fails wait for 5, 10, 15, ... seconds and try again.
def download_xml (url, tries = 1):
    try: 
        response = urllib.request.urlopen(url)
    except:
        print('Something went wrong. Wait for 5 seconds and try again.', tries)
        if tries < 5:
            time.sleep(5 * tries)
            download_xml(url, tries + 1)
    else:     
        # decode the response into a string
        data = response.read().decode('utf-8')
        # set up the regular expression extractoer in order to get the relevant part of the filing
        matcher = re.compile('<\?xml.*ownershipDocument>', flags=re.MULTILINE|re.DOTALL)
        matches = matcher.search(data)
        # the first matching group is the extracted XML of interest
        xml = matches.group(0)
        # instantiate the XML object
        root = ET.fromstring(xml)
        print(url)
        return root 
        
# Calculate the total transaction amount in $ of a giving form 4 in XML
def calculate_transaction_amount (xml):
    total = 0
    
    if xml is None:
        return total
    
    nonDerivativeTransactions = xml.findall("./nonDerivativeTable/nonDerivativeTransaction")

    for t in nonDerivativeTransactions:
        # D for disposed or A for acquired
        action = t.find('./transactionAmounts/transactionAcquiredDisposedCode/value').text
        # number of shares disposed/acquired
        shares = t.find('./transactionAmounts/transactionShares/value').text
        # price
        priceRaw = t.find('./transactionAmounts/transactionPricePerShare/value')
        price = 0 if priceRaw is None else priceRaw.text
        # set prefix to -1 if derivatives were disposed. set prefix to 1 if derivates were acquired.
        prefix = -1 if action == 'D' else 1
        # calculate transaction amount in $
        amount = prefix * float(shares) * float(price)
        total += amount
    
    return round(total, 2)