PyGMT: Coloring pixels of a specific elevation

With PyGMT, is there a way to color the pixels of a raster at a specific elevation with cmap? I’d like to, say, color only the 50m elevation pixels.

I am not sure if this is the best solution, but I would probably just clip the grip to only include values equal 50 for plotting. Here is an example:

import numpy as np
import pygmt
import xarray as xr

# Define a function of two variables
def sumgrid(x, y):
    return (
        x + y
    )

# Create gridded data
INC = 0.2
x = np.arange(0, 50 + INC, INC)
y = np.arange(0, 50 + INC, INC)
data = xr.DataArray(sumgrid(*np.meshgrid(x, y)), coords=(x, y))
data_clip = pygmt.grdclip(grid=data, above="50/NaN", below="50/NaN")

fig = pygmt.Figure()
# Plot grid
fig.grdimage(
    grid=data,
    projection="X10c",
    region=[0,50,0,50],
    frame=True,
    cmap="gray"
)
pygmt.makecpt(cmap="hot", series=[45,55,10])
fig.grdimage(
    grid=data_clip,
    cmap=True,
    nan_transparent=True
)

fig.show()