sys.argv[1] IndexError: list index out of range
<p>When running the program below from a command prompt in windows it keeps displaying the 'IndexError: list Index out of range', even when I am definitely adding a number argument eg.<strong>'bigdigits.py 123'</strong></p>

<p>The program runs fine if I assign a string to 'digits' manually in the program eg. <strong>digits = '123'.</strong></p>

<pre><code>import sys

Zero = [" *** ", "*   *", "*   *", "*   *", "*   *", "*   *", " *** "]  
One = [" **  ", "  *  ", "  *  ", "  *  ", "  *  ", "  *  ", " *** "]  
Two = [" **   ", "*  * ", "   * ", "  *  ", " *   ", "*    ", "**** "]  
Three = ["*****", "   * ", "  *  ", " *** ", "    *", "*   *", " *** "]  
Four = ["  *  ", " **  ", "* *  ", "*****", "  *  ", "  *  ", "  *  "]  
Five = ["*****", "*    ", "***  ", "   * ", "    *", "*   *", " *** "]  
Six = ["  ** ", " *   ", "*    ", "***  ", "*  * ", "*  * ", " **  "]  
Seven = ["*****", "    *", "   * ", "  *  ", " *   ", " *   ", " *   "]  
Eight = [" *** ", "*   *", "*   *", " *** ", "*   *", "*   *", " *** "]  
Nine = [" *** ", "*   *", "*   *", " *** ", "  *  ", " *   ", "*    "]  

Digits = [Zero, One, Two, Three, Four, Five, Six, Seven, Eight, Nine]

try:  
    digits = sys.argv[1]  
    row = 0  
    while row &lt; 7:  
        line = ""  
        column = 0  
        while column &lt; len(digits):  
            number = int(digits[column])  
            digit = Digits[number]  
            line += digit[row] + " "  
            column += 1  
        print(line)  
        row += 1  

except ValueError as err:  
    print(err, "in", digits) 
</code></pre>
