"Error: No module named 'bcolz'." but bcolz is already installed

I have tried a bunch of solutions listed below but still get the same error. Any ideas?

conda install -c anaconda bcolz
pip install conda

source activate my_conda_env
(my_conda_env) $ conda install nb_conda


ModuleNotFoundError Traceback (most recent call last)
in ()
1 # This file contains all the main external libs we’ll use
----> 2 from fastai.imports import *

~/sample-notebooks/fastai/courses/dl1/fastai/imports.py in ()
1 from IPython.lib.deepreload import reload as dreload
----> 2 import PIL, os, numpy as np, math, collections, threading, json, bcolz, random, scipy, cv2
3 import random, pandas as pd, pickle, sys, itertools, string, sys, re, datetime, time, shutil
4 import seaborn as sns, matplotlib
5 import IPython, graphviz, sklearn_pandas, sklearn, warnings

ModuleNotFoundError: No module named ‘bcolz’