Python String Formatting

There are several ways to format strings correctly.

Using the % operator

name = "Alice"
age = 30
formatted_string = "My name is %s and I am %d years old." % (name, age)
print(formatted_string)  # Output: My name is Alice and I am 30 years old.

Using str.format() method 

name = "Alice"
age = 30
formatted_string = "My name is {} and I am {} years old.".format(name, age)
print(formatted_string)  # Output: My name is Alice and I am 30 years old.

Using f-strings (formatted string literals) (Python 3.6+) 

name = "Alice"
age = 30
formatted_string = f"My name is {name} and I am {age} years old."
print(formatted_string)  # Output: My name is Alice and I am 30 years old.

Using template strings with string.Template 

name = "Alice"
age = 30
from string import Template
template = Template("My name is $name and I am $age years old.")
formatted_string = template.substitute(name=name, age=age)
print(formatted_string)  # Output: My name is Alice and I am 30 years old.

Using concatenation with + operator 

name = "Alice"
age = 30
formatted_string = "My name is " + name + " and I am " + str(age) + " years old."
print(formatted_string)  # Output: My name is Alice and I am 30 years old.

Using join method 

name = "Alice"
age = 30
formatted_string = " ".join(["My name is", name, "and I am", str(age), "years old."])
print(formatted_string)  # Output: My name is Alice and I am 30 years old.

Using printf-style formatting with dictionary 

name = "Alice"
age = 30
data = {"name": name, "age": age}
formatted_string = "My name is %(name)s and I am %(age)d years old." % data
print(formatted_string)  # Output: My name is Alice and I am 30 years old.

Using str.format_map with dictionary 

name = "Alice"
age = 30
formatted_string = "My name is {name} and I am {age} years old.".format_map(data)
print(formatted_string)  # Output: My name is Alice and I am 30 years old.

These methods cover the most common ways to format strings in Python, each useful in different contexts and versions of Python.