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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 add_gwb(psr, dist=1, ngw=1000, seed=None, flow=1e-8, fhigh=1e-5, gwAmp=1e-20, alpha=-0.66, logspacing=True):
 """Add a stochastic background from inspiraling binaries, using the tempo2 code that underlies the GWbkgrd plugin. Here 'dist' is the pulsar distance [in kpc]; 'ngw' is the number of binaries, 'seed' (a negative integer) reseeds the GWbkgrd pseudorandom-number-generator, 'flow' and 'fhigh' [Hz] determine the background band, 'gwAmp' and 'alpha' determine its amplitude and exponent, and setting 'logspacing' to False will use linear spacing for the individual sources. It is also possible to create a background object with gwb = GWB(ngw,seed,flow,fhigh,gwAmp,alpha,logspacing) then call the method gwb.add_gwb(pulsar[i],dist) repeatedly to get a consistent background for multiple pulsars. Returns the GWB object """

    
    gwb = GWB(ngw,seed,flow,fhigh,gwAmp,alpha,logspacing)
    gwb.add_gwb(psr,dist)

    return gwb