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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def generate_iucv_authfile(fn, client):
 """Generate the iucv_authorized_userid file"""

    lines = ['#!/bin/bash\n',
             'echo -n %s > /etc/iucv_authorized_userid\n' % client]
    with open(fn, 'w') as f:
        f.writelines(lines)