Python中如何修改print()输出函数（含多返回值）的显示格式？

Hey there! Let's break down your two Python print formatting questions with practical, easy-to-follow examples:

There are several flexible ways to tweak how print() displays content—here are the most common, useful approaches:

• Use the built-in sep and end parameters
  By default, print() separates multiple arguments with spaces and ends with a newline. You can override these to match your needs:

  # Change the separator between values
  print(1, 2, 3, sep=" | ")  # Output: 1 | 2 | 3
  
  # Replace the default newline ending with something else
  print("Hi there", end="! ")
  print("How are you?")  # Output: Hi there! How are you?
  

• String formatting (f-strings, str.format(), or old-style % formatting)
  For precise control over value display (like decimal places, padding, or text wrapping), use string formatting:

  pi = 3.14159
  # F-strings (Python 3.6+) – the most readable option
  print(f"Pi rounded to 2 decimals: {pi:.2f}")  # Output: Pi rounded to 2 decimals: 3.14
  
  # str.format() method (works for older Python versions)
  print("Pi rounded to 2 decimals: {:.2f}".format(pi))  # Same output as above
  
  # Old-style % formatting (legacy, but still functional)
  print("Pi rounded to 2 decimals: %.2f" % pi)
  

• Create a custom print function
  If you want a consistent custom format across your codebase, wrap the built-in print() with your own logic:

  def custom_print(*args, sep=" | ", end="\n", file=None):
      # Example: Convert all inputs to uppercase before printing
      processed_args = [str(arg).upper() for arg in args]
      # Call the original print function with modified arguments
      print(*processed_args, sep=sep, end=end, file=file)
  
  custom_print("hello", "python world")  # Output: HELLO | PYTHON WORLD
  

First, a quick clarification: when a Python function returns multiple values like return x, y, it's actually returning a tuple—that's why print(test()) outputs (2, 4). Here are simple ways to reformat that output:

• Unpack the tuple directly in print()
  Use the * operator to unpack the tuple into separate arguments for print(), then set sep to " and ":

  def test():
      x = 1 + 1
      y = 2 + 2
      return x, y
  
  print(*test(), sep=" and ")  # Output: 2 and 4
  

  This works for tuples of any length—if your function returns 3 values, it'll automatically output a and b and c.

• Unpack and format with f-strings
  If you need to reuse the returned values later, unpack them first then format:

  a, b = test()
  print(f"{a} and {b}")  # Output: 2 and 4
  

  This is great for readability and gives you access to a and b for other code logic.

• String join for variable-length tuples
  For tuples where the number of elements might change, convert each element to a string and join them:

  result = test()
  print(" and ".join(map(str, result)))  # Output: 2 and 4
  

  This works seamlessly whether your function returns 2, 3, or more values.

内容的提问来源于stack exchange，提问作者Lis