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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 _x_for_spln(x, nx, log_spacing):
 """ Create vector of values to be used in constructing a spline. Parameters x : num | num iterable Resulted values will span the range [min(x), max(x)] nx : int Length of returned vector. log_spacing: bool False - Create linearly spaced values. True - Create logarithmically spaced values. To extend to negative values, the spacing is done separately on the negative and positive range, and these are later combined. The number of points in the negative/positive range is proportional to their relative range in log space. i.e., for data in the range [-100, 1000] 2/5 of the resulting points will be in the negative range. Returns ------- x_spln : array """

    x = asarray(x)
    xmin = min(x)
    xmax = max(x)
    if xmin == xmax:
        return asarray([xmin] * nx)
    if xmax <= 0:  # all values<=0
        return -_x_for_spln(-x, nx, log_spacing)[::-1]

    if not log_spacing:
        return linspace(xmin, xmax, nx)

    # All code below is to handle-log-spacing when x has potentially both negative
    # and positive values.
    if xmin > 0:
        return logspace(log10(xmin), log10(xmax), nx)
    else:
        lxmax = max([log10(xmax), 0])
        lxmin = max([log10(abs(xmin)), 0])

        # All the code below is for log-spacing, when xmin < 0 and xmax > 0
        if lxmax == 0 and lxmin == 0:
            return linspace(xmin, xmax, nx)  # Use linear spacing as fallback

        if xmin > 0:
            x_spln = logspace(lxmin, lxmax, nx)
        elif xmin == 0:
            x_spln = r_[0, logspace(-1, lxmax, nx - 1)]
        else:  # (xmin < 0)
            f = lxmin / (lxmin + lxmax)
            nx_neg = int(f * nx)
            nx_pos = nx - nx_neg

            if nx <= 1:
                # If triggered fix edge case behavior
                raise AssertionError(u'nx should never bebe 0 or 1')

            # Work-around various edge cases
            if nx_neg == 0:
                nx_neg = 1
                nx_pos = nx_pos - 1

            if nx_pos == 0:
                nx_pos = 1
                nx_neg = nx_neg - 1

            x_spln_pos = logspace(-1, lxmax, nx_pos)
            x_spln_neg = -logspace(lxmin, -1, nx_neg)

            x_spln = r_[x_spln_neg, x_spln_pos]
    return x_spln