import hou

# Get the current network editor and the location to place the note
network_editor = hou.ui.paneTabOfType(hou.paneTabType.NetworkEditor)
pos = network_editor.visibleBounds().center()


# Create the note node
note = network_editor.pwd().createStickyNote()
note.setTextColor(hou.Color(1.0, 1.0, 1.0))
note.setTextSize(2.0)
note.setText("This is a new note.")
note.setDrawBackground(0)

# Position the note in the center of the current view
note.setPosition(pos)