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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 report_onlysize(bytes_so_far, total_size, speed, eta):
    '''
    This callback for the download function is used when console width
    is not enough to print the bar.
    It prints only the sizes
    '''
    percent = int(bytes_so_far * 100 / total_size)
    current = approximate_size(bytes_so_far).center(10)
    total = approximate_size(total_size).center(10)
    sys.stdout.write('D: {0}% -{1}/{2}'.format(percent, current, total) + "eta {0}".format(eta))
    sys.stdout.write("\r")
    sys.stdout.flush()