请写一段代码，使用Python的Spacy训练聊天机器人

以下是使用Python的Spacy训练聊天机器人的代码：

import spacy
from spacy import displacy
from spacy.matcher import Matcher
from spacy.tokens import Span

nlp = spacy.load("en_core_web_sm")

# Define the pattern for the matcher
pattern = [{"LOWER": "hello"}, {"IS_PUNCT": True}, {"LOWER": "world"}]

# Initialize the matcher and add the pattern
matcher = Matcher(nlp.vocab)
matcher.add("HelloWorld", None, pattern)

# Define the callback function for the matcher
def on_match(matcher, doc, id, matches):
    match_id, start, end = matches[id]
    span = Span(doc, start, end)
    print("Matched phrase:", span.text)

# Add the callback function to the matcher
matcher.add("HelloWorld", on_match, pattern)

# Test the matcher on a sample text
doc = nlp("Hello, world! This is a sample text.")
matches = matcher(doc)

这段代码使用了Spacy库来训练一个聊天机器人，它会匹配包含"hello, world"的短语，并在匹配时输出匹配的短语。