moviepy: Unable to run the sample code! Getting errors. Plase Help

Hi there, I tried to run the sample/example code for the moviePy but I’m getting this error. I don’t know how to resolve. I’m an novice in the field so don’t have an experience like you guys.

from moviepy.editor import *
clip = VideoFileClip("myHolidays.mp4").subclip(5,15)
clip = clip.volumex(0.8)
txt_clip = TextClip("My Holidays 2013",fontsize=70,color='white')
txt_clip = txt_clip.set_pos('center').set_duration(10)
video = CompositeVideoClip([clip, txt_clip])
video.write_videofile("myHolidays_edited.avi")

Error message:

[MoviePy] This command returned an error !
Traceback (most recent call last):
  File "/home/pi/clip_example.py", line 11, in <module>
    txt_clip = TextClip("My Holidays 2013",fontsize=70,color='white')
  File "/usr/local/lib/python2.7/dist-packages/moviepy/video/VideoClip.py", line 1173, in __init__
    raise IOError(error)
IOError: MoviePy Error: creation of None failed because of the following error:

convert: not authorized `@/tmp/tmpIJUQvL.txt' @ error/property.c/InterpretImageProperties/3405.
convert: no images defined `PNG32:/tmp/tmpt9CCfR.png' @ error/convert.c/ConvertImageCommand/3210.
.

.This error can be due to the fact that ImageMagick is not installed on your computer, or (for Windows users) that you didn't specify the path to the ImageMagick binary in file conf.py, or.that the path you specified is incorrect