Problem with the use of python classes

When I run my program it gives me this error:

  

new = colony.Colonia (self .__ tasks, self .__ times)   UnboundLocalError: local variable 'colony' referenced before assignment

my class is the following:

import tareas
import hormiga
import colonia
class inicio:
def __init__(self):
    self.__nHormigas = 20 #mAnts
    self.__veces = 4 #mIter
    self.__generaciones = 500 #mHillsCount
    self.__alfa = 1
    self.__beta = 1 
    self.__p = 0.1 #mEvap
    self.__nTareas = 100
    self.__mColonia = [] #mHills
    self.__tareas = []
    self.__mMejorRuta = []

def getMejorCoste(self):
    return self.__mejorCoste #mBestCost

def getRuta(self):
    return self.__mMejorRuta #mBestPath

def Iniciar(self):
    self.__mejorCoste = float('inf')
    for e in range(self.__nTareas):
        tarea = tareas.Tarea()
        self.__tareas.append(tarea)
    for i in range(self.__generaciones):
        nueva = colonia.Colonia(self.__tareas,self.__veces) #aquí es el error
        self.__mColonia.append(nueva)
    #en paralelo??
    for colonia in self.__mColonia:
        colonia.empezar()
    self.__mColonia.sort(key=lambda x: x.getMejorCoste())
    if (self.__mColonia[0].getMejorCoste() < self.__mejorCoste):
        self.__mejorCoste = self.__mColonia[0].getMejorCoste()
        self.__mMejorRuta = []
        for tarea in self.__mColonia[0].getMejorRuta():
            self.__mMejorRuta.append(tarea)
    print(self.__mejorCoste)

My file directory contains one called colonia.py whose constructor is the following:

class Colonia:
def __init__ (self, tareas, n_iteraciones, evaporacion=0.1, n_hormigas=20):
    self.__constanteEvaporacion = evaporacion
    self.__nHormigas = n_hormigas
    self.__iteraciones = n_iteraciones
    self.__evaporacion = 1.0 - evaporacion
    self.__tareas = tareas

    self.__mejorCoste = float('inf')
    self.__mejorRuta = list()
    self.__hormigas = []
    #inicializamos matriz de feromonas
    self.__mFeromonas = [[getValorInicialFeromona()]*len(self.__tareas) for x in range(len(self.__tareas))]
    self.__feromonas = [[0.0]*len(self.__tareas) for x in range(len(self.__tareas))]

my directory.

Any ideas?

Thank you.