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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 tree(c):
 """ Display documentation contents with the 'tree' program. """

    ignore = ".git|*.pyc|*.swp|dist|*.egg-info|_static|_build|_templates"
    c.run('tree -Ca -I "{0}" {1}'.format(ignore, c.sphinx.source))