code: def build_defines(defines):
      
  
      return ['-D"%s=%s"' % (x, str(y)) for x, y in defines.items() if y is not None]
docs: Build a list of `-D` directives to pass to the compiler.
  
      This will drop any definitions whose value is None so that
      you can get rid of a define from another architecture by
      setting its value to null in the `module_settings.json`.