Please answer the following question: Extract the answer to the following question from the movie plot. If the question isn't answerable, please output "Can't answer". Question: who checks his mailbox for Christmas cards? Title: A Charlie Brown Christmas Movie plot: The special begins on a frozen pond, put to use as an ice rink by the Peanuts cast, who skate together as the song "Christmas Time Is Here" is heard over the opening credits. It's Christmas season, and Charlie Brown is depressed. He confides in Linus this fact, citing his dismay with the over-commercialization of Christmas and his inability to grasp what Christmas is all about; Linus dismisses it as typical Charlie Brown behavior at first. Brown's depression and aggravation only get exacerbated by the goings-on in the neighborhood. Though his mailbox is empty, he tries sarcastically to thank Violet for the card she never sent him, but Violet just uses the opportunity to put Brown down again. Eventually, Charlie Brown visits Lucy in her psychiatric booth. Lucy, after presumptively diagnosing him with various phobias and admitting she wants real estate as a Christmas gift, determines that Charlie Brown needs more involvement and recommends that he direct a Christmas play. On his way to the auditorium, he finds his dog Snoopy decorating his doghouse for a neighborhood lights and display contest. En route to the rehearsals, he runs into his sister Sally, who asks him to write her letter to Santa Claus. When she tells him to put in a request for money ("tens and twenties"), Charlie Brown becomes even more dismayed. Charlie Brown arrives at the rehearsals, but he is unable to control the situation as the uncooperative kids are more interested in modernizing the play with dancing and lively music, mainly Schroeder's rendition of "Linus and Lucy." Thinking the play requires "the proper mood," Charlie Brown decides they need a Christmas tree. Lucy takes over the crowd and dispatches Charlie Brown to get a "big, shiny aluminum tree." With Linus in tow, Charlie Brown sets off on his quest, as an "O Tannenbaum" instrumental plays in the background. When they get to the tree market, filled with numerous trees fitting Lucy's description, Charlie Brown zeroes in on the only real tree on the lota tiny sapling. Linus is...
A:
Charlie Brown