If you do not want to see the ECMWF logo on your plot, set the parameter page_id_line to off in the page object.

from Magics.macro import *

#Setting output
output = output(
    output_formats                = ['ps'],
    output_name                   = 'precip',
    output_name_first_page_number = 'off')
#Setting the coastlines
background = mcoast(
    map_coastline_land_shade        = 'on',
    map_coastline_land_shade_colour = 'cream')
#Setting data
grib = mgrib(grib_input_file_name = "path/data.grib")
#Defining the contour
contour = mcont(
)
#Plotting
plot(output, background, grib, data)