import sys
import pylab
import numpy
import time

def test():
    data=numpy.linspace(0,1000,100)
    pylab.figure(14)
    pylab.plot(data,data)
    pylab.savefig('foo.png')
    # if next step is commented out then the error is not produced
    pylab.close(14)

def doit(filename='foo'):
    for i in range(2):
        test()

# Next lines permit one to run the routine from the command line
if __name__ == "__main__":
    import sys
    doit()