It's already easy to expose a python function as an MCP server. From the fastmcp docs:

  from fastmcp import FastMCP
  
  mcp = FastMCP("Demo ")
  
  @mcp.tool
  def add(a: int, b: int) -> int:
      """Add two numbers"""
      return a + b
  
  if __name__ == "__main__":
      mcp.run()