The common module
 The gomill.common module provides Go-related utility functions, used throughout Gomill.
It is designed to be safe to use as from common import *.
-  gomill.common.opponent_of(colour)[source]
- Return type: - colour - Returns the other colour: - >>> opponent_of('b') 'w' 
-  gomill.common.colour_name(colour)[source]
- Return type: - string - Returns the (lower-case) full name of a colour: - >>> colour_name('b') 'black' 
-  gomill.common.format_vertex(move)[source]
- Return type: - string - Returns a string describing a move in conventional notation: - >>> format_vertex((3, 0)) 'A4' >>> format_vertex(None) 'pass' - The result is suitable for use directly in GTP responses. Note that - Iis omitted from the letters used to indicate columns, so the maximum supported column value is- 25.
-  gomill.common.format_vertex_list(moves)[source]
- Return type: - string - Returns a string describing a sequence of moves: - >>> format_vertex_list([(0, 1), (2, 3), None]) 'B1,D3,pass' >>> format_vertex_list([]) '' 
-  gomill.common.move_from_vertex(vertex, board_size)[source]
- Return type: - move - Interprets the string vertex as conventional notation, assuming a square board whose side is board_size: - >>> move_from_vertex("A4", 9) (3, 0) >>> move_from_vertex("a4", 9) (3, 0) >>> move_from_vertex("pass", 9) None - Raises - ValueErrorif it can’t parse the string, or if the resulting point would be off the board.- Treats vertex case-insensitively.