[Python] Python's many ways of string formatting — are the older ones (going to be) deprecated?

Python has at least seven ways of formatting a string:

In [1]: world = "Earth"

# method 1a
In [2]: "Hello, %s" % world
Out[2]: 'Hello, Earth'

# method 1b
In [3]: "Hello, %(planet)s" % {"planet": world}
Out[3]: 'Hello, Earth'

# method 2a
In [4]: "Hello, {0}".format(world)
Out[4]: 'Hello, Earth'

# method 2b
In [5]: "Hello, {planet}".format(planet=world)
Out[5]: 'Hello, Earth'

# method 2c
In [6]: f"Hello, {world}"
Out[6]: 'Hello, Earth'

In [7]: from string import Template

# method 3
In [8]: Template("Hello, $planet").substitute(planet=world)
Out[8]: 'Hello, Earth'


Method 4: template strings.

A brief history of the different methods:

• printf-style formatting has been around since Pythons infancy
• The Template class was introduced in Python 2.4
• The format method was introduced in Python 2.6
• f-strings were introduced in Python 3.6
• t-strings were introduced in Python 3.14

My questions are:

• Is printf-style formatting deprecated or going to be deprecated?
• In the Template class, is the substitute method deprecated or going to be deprecated? (I'm not talking about safe_substitute, which as I understand it offers unique capabilities)

Similar questions and why I think they're not duplicates:

• 
  String formatting: % vs. .format vs. f-string literal — treats only methods 1 and 2, and asks which one is better; my question is explicitly about deprecation in the light of the Zen of Python
  
  
• 
  String formatting options: pros and cons — treats only methods 1a and 1b in the question, 1 and 2 in the answer, and also nothing about deprecation
  
  
• 
  advanced string formatting vs template strings — mostly about methods 1 and 3, and doesn't address deprecation
  
  
• 
  String formatting expressions (Python) — answer mentions that the original '%' approach is planned to be deprecated. But what's the difference between planned to be deprecated, pending deprecation and actual deprecation? And the printf-style method doesn't raise even a PendingDeprecationWarning, so is this really going to be deprecated? This post is also quite old, so the information may be outdated.
  

See also

• PEP 502: String Interpolation - Extended Discussion
• String Formatter

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