Qt Code: 
  1. from PyQt5.QtCore import QObject, QTimer, pyqtSignal
  2. from urllib import request
  3. import xml.etree.ElementTree as ET
  4. from datetime import datetime, time
  5.  
  6. class SignalSource(QObject):
  7.     valuesChecked = pyqtSignal(dict)
  8.  
  9.     def __init__(self, xmlUrl, timerIntervalMs=10):
  10.         QObject.__init__(self)
  11.         self.xmlUrl = xmlUrl
  12.         self.timer = QTimer()
  13.         self.timer.setInterval(timerIntervalMs)
  14.         self.timer.timeout.connect(self.timerFires)
  15.         self.timer.start()
  16.  
  17.         self.sample = {}
  18.  
  19.     def getSample(self, sourcePiece):
  20.         return self.sample[sourcePiece[0], sourcePiece[1]]
  21.  
  22.     def timerFires(self):
  23.         response = request.urlopen(self.xmlUrl)
  24.         xmlStr = response.read()
  25.         root = ET.fromstring(xmlStr)
  26.  
  27.         for child in root:
  28.             asset = child.attrib["Symbol"]
  29.             self.sample[asset] = { 
  30.                 "bid": float(child.find("Bid").text), 
  31.                 "ask": float(child.find("Ask").text),
  32.                 "high": float(child.find("High").text),
  33.                 "low": float(child.find("Low").text),
  34.                 "@ last": time(child.find("Last").text),
  35.                 "direction": int(child.find("Direction").text),
  36.                 }
  37.         self.valuesChecked.emit(self.sample)
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I simply call
signalSource = SignalSource("myXmlUrl")
inside the main debug module at module scope.

No timer firing action, so I never get to take a sample :'(