input: Write a function to port a given Java code snippet to Python 3. The function should take the Java code as input, process it, and return the equivalent Python 3 code. 
  assert port_java_to_python("public class Foo { public int foo( int a, int b ) { return a + b; } }")=='def foo(a, b):\n return a + b'
  assert port_java_to_python("public class Bar { public void bar() { System.out.println(\"Hello\"); } }")=="def bar():\n print('Hello')"
  assert port_java_to_python("")==''
  assert port_java_to_python("public class Empty {}")==''
  assert port_java_to_python("public class Complex { public int complexOperation(int x, int y) { return x * y + x - y; } }")=='def complexOperation(x, y):\n return x * y + x - y'
output: def port_java_to_python(java_code):
      import re
      method_pattern = re.compile(r'public\s+(\w+)\s+(\w+)\s*\(([^)]*)\)\s*{([^}]*)}')
      methods = method_pattern.findall(java_code)
      python_code = []
      for method in methods:
          return_type, name, params, body = method
          params = [p.strip().split()[-1] for p in params.split(',')] if params else []
          params_str = ', '.join(params)
          body = body.strip().replace('System.out.println', 'print').replace(';', '')
          if return_type != 'void':
              body = body.replace('return ', '').strip()
              body = f'return {body}'
          python_code.append(f'def {name}({params_str}):\n {body}')
      return '\n'.join(python_code)