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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_rates(file,au_min=25,au_max=150):
 """ Use the rates program to determine the minimum and maximum bounds for planting"""

    import os, string

    rate_command='rate.pl --file %s %d ' % ( file, au_min)
    rate=os.popen(rate_command)
    line=rate.readline()
    print line
    rate.close()
    (min_rate, min_ang, min_aw, min_rmin, min_rmax)=string.split(line)
    rate_command='rate.pl --file %s %d ' % ( file, au_min)
    rate=os.popen(rate_command)
    line=rate.readline()
    rate.close()
    (max_rate, max_ang, max_aw, max_rmin, max_rmax)=string.split(line)
    rmin=float(min(max_rmin, min_rmin))
    rmax=float(max(max_rmax, min_rmax))
    aw=float(max(max_aw,min_aw))
    angle=(float(max_ang)+float(min_ang))/2.0
    rates={'rmin': rmin, 'rmax': rmax, 'angle': angle, 'aw': aw}
    return rates