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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 windyields(self, ini, end, delta, **keyw):
 """ This function returns the wind yields and ejected masses. X_i, E_i = data.windyields(ini, end, delta) Parameters ini : integer The starting cycle. end : integer The finishing cycle. delta : integer The cycle interval. keyw : dict A dict of key word arguments. Returns ------- list The function returns a list of the wind yields(X_i) and a list of the ejected masses(E_i) in the mass units that were used (usually solar masses). Notes ----- The following keywords cand also be used: | Keyword Argument | Default Value | +==================+===============+ | abund | "iso_massf" | | tmass | "mass" | | cycle | "cycle" | The keyword arguments are used when the variables within the input file differ in name from their default values typically found in an MPPNP output file. If the data table differs in name, use these keywords. For example, if the table for the abundances is called "abundances" instead of "iso_massf", then use abund = "abundances" as a keyword argument. """


        if ("tmass" in keyw) == False:
            keyw["tmass"] = "mass"
        if ("abund" in keyw) == False:
            keyw["abund"] = "iso_massf"
        if ("cycle" in keyw) == False:
            keyw["cycle"] = "cycle"

        print("Windyields() initialised.  Reading files...")

        ypsinit = []
        niso = 0
        X_i = []
        E_i = []
        totalmass = []
        ypssurf  = []
        cycles = []
        first = True

        # The following statements copy global functions into local memory,
        # which is called faster, speeding up the code slightly
        wc = self._windcalc
        cycleret = self.se.cycles
        retrieve = self.se.get
        capp = cycles.extend
        tapp = totalmass.extend
        yapp = ypssurf.extend

        # Retrieve the data from the files
        for i in range(ini,end+1,delta):
            step = int(i)
            capp([int(cycleret[i-ini])])
            tapp([retrieve(step,keyw["tmass"])])
            yapp([retrieve(step,keyw["abund"])])

        print("Reading complete.  Calculating yields and ejected masses...")

        nsteps = len(cycles)-1
        niso = len(ypssurf[0])
        X_i = np.zeros([niso], float)
        E_i = np.zeros([niso], float)
        # Call the windyields calculator
        X_i, E_i = wc(first, totalmass, nsteps, niso, ypssurf, \
        ypsinit, X_i, E_i, cycles)
        return X_i, E_i