def get_normalization_scale(norm, norm_min, norm_max, linthresh, linscale):
if norm is '<STR_LIT>':<EOL><INDENT>return colors.Normalize(vmin=norm_min, vmax=norm_max)<EOL><DEDENT>elif norm is '<STR_LIT>':<EOL><INDENT>if norm_min == <NUM_LIT:0.0>:<EOL><INDENT>norm_min = <NUM_LIT><EOL><DEDENT>return colors.LogNorm(vmin=norm_min, vmax=norm_max)<EOL><DEDENT>elif norm is '<STR_LIT>':<EOL><INDENT>return colors.SymLogNorm(linthresh=linthresh, linscale=linscale, vmin=norm_min, vmax=norm_max)<EOL><DEDENT>else:<EOL><INDENT>raise exc.PlottingException('<STR_LIT>'<EOL>'<STR_LIT>')<EOL><DEDENT>
Get the normalization scale of the colormap. This will be scaled based on the input min / max normalization \
    values.

    For a 'symmetric_log' colormap, linthesh and linscale also change the colormap.

    If norm_min / norm_max are not supplied, the minimum / maximum values of the array of data are used.

    Parameters
    -----------
    array : data.array.scaled_array.ScaledArray
        The 2D array of data which is plotted.
    norm_min : float or None
        The minimum array value the colormap map spans (all values below this value are plotted the same color).
    norm_max : float or None
        The maximum array value the colormap map spans (all values above this value are plotted the same color).
    linthresh : float
        For the 'symmetric_log' colormap normalization ,this specifies the range of values within which the colormap \
        is linear.
    linscale : float
        For the 'symmetric_log' colormap normalization, this allowws the linear range set by linthresh to be stretched \
        relative to the logarithmic range.