在给定的文本中查找关键词并返回它们的出现次数。


文本: Python is a widely used high-level programming language for general-purpose programming, created by Guido van Rossum and first released in 1991. 
关键词: programming, created, 1991
程序将从给定文本中统计三个关键词的出现次数: programming、created 和 1991。它将返回每个关键词的出现次数。