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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 apply(self, a, return_Ya=False):
 r"""Apply the projection to an array. The computation is carried out without explicitly forming the matrix corresponding to the projection (which would be an array with ``shape==(N,N)``). See also :py:meth:`_apply`. """

        # is projection the zero operator?
        if self.V.shape[1] == 0:
            Pa = numpy.zeros(a.shape)
            if return_Ya:
                return Pa, numpy.zeros((0, a.shape[1]))
            return Pa
        if return_Ya:
            x, Ya = self._apply(a, return_Ya=return_Ya)
        else:
            x = self._apply(a)
        for i in range(self.iterations-1):
            z = a - x
            w = self._apply(z)
            x = x + w
        if return_Ya:
            return x, Ya
        return x