Section 12020, subdivision (a), makes it a crime for any person to carry a dirk or dagger "concealed upon his or her person . . . ." Subdivision (c)(24) of that section defines dirk or dagger as "a knife or other instrument with or without a handguard that is capable of ready use as a stabbing weapon that may inflict great bodily injury or death." The dirk or dagger need not be entirely concealed; substantial concealment is sufficient. (People v. Wharton (1992) 5 Cal. App. 4th 72, 75.)