Conexion.py

#!/usr/bin/python

import time
from time import sleep
import serial
import random

class Conexion:
    puerto_serie = None

    def __init__(self):
        return None
        #self.conectar()

    def conectar(self):
        self.puerto_serie = serial.Serial('/dev/ttyACM0',
                                          baudrate=9600,
                                          bytesize=serial.EIGHTBITS,
                                          parity=serial.PARITY_NONE,
                                          stopbits=serial.STOPBITS_ONE,
                                          timeout=1,
                                          xonxoff=0,
                                          rtscts=0
                                          )

    def close(self):
        self.puerto_serie.close()

    def lectura(self):
        self.puerto_serie.setDTR(True)  # indica que el canal esta listo para comunicarse
        sleep(5)
        lectura = self.puerto_serie.readline().strip()
        lectura.decode("utf-8")
        print("esta es: ")
        print(lectura)
        print(time.strftime("%c"))

        lectura = float(lectura.replace(',', '.'))
        return lectura
        return round(random.uniform(27, 28), 2)