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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 get(ctx, key):
    '''Retrieve the value for the given key.'''
    file = ctx.obj['FILE']
    stored_value = get_key(file, key)
    if stored_value:
        click.echo('%s=%s' % (key, stored_value))
    else:
        exit(1)