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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 exist(name):
    '''
    Return True if the chroot environment is present.
    '''
    dev = os.path.join(name, 'dev')
    proc = os.path.join(name, 'proc')
    return all(os.path.isdir(i) for i in (name, dev, proc))