Format strings using Python dict

In Python, you can use dictionaries to format strings. The str.format() method allows you to substitute placeholders in a string with values from a dictionary. To do this, you need to use named placeholders in the string and pass the dictionary to the str.format() method using the ** unpacking operator.

Here's an example:

person = {'name': 'John', 'age': 30, 'city': 'New York'}

# Using named placeholders in the string
formatted_string = "{name} is {age} years old and lives in {city}."

# Pass the dictionary to the str.format() method using the ** unpacking operator
result = formatted_string.format(**person)
print(result)  # Output: John is 30 years old and lives in New York.

In this example, the formatted_string contains named placeholders ({name}, {age}, and {city}) that correspond to the keys in the person dictionary. The str.format() method substitutes the placeholders with the respective values from the person dictionary.

Alternatively, starting from Python 3.6, you can use f-strings (formatted string literals) to achieve the same result:

person = {'name': 'John', 'age': 30, 'city': 'New York'}

# Using f-string with dictionary keys
result = f"{person['name']} is {person['age']} years old and lives in {person['city']}."
print(result)  # Output: John is 30 years old and lives in New York.

In this example, the f-string directly accesses the dictionary keys within the string. The expressions inside the curly braces {} are evaluated at runtime and then formatted according to the specified format options.

Python String Formatting with Dictionaries:
- String formatting allows embedding variables or values into strings.
- Dictionaries provide a convenient way to organize and use key-value pairs for formatting.
```
# Example
person_info = {'name': 'John', 'age': 25}
formatted_string = "Name: {name}, Age: {age}".format(**person_info)
```

How to Format Strings Using Python Dict:

Use the format() method and provide dictionary values as arguments.

# Example
person_info = {'name': 'Alice', 'age': 30}
formatted_string = "Name: {name}, Age: {age}".format(name=person_info['name'], age=person_info['age'])

Dictionary-Based String Interpolation in Python:

Interpolate dictionary values directly into strings.

# Example
person_info = {'name': 'Bob', 'age': 28}
interpolated_string = f"Name: {person_info['name']}, Age: {person_info['age']}"

String Formatting with Key-Value Pairs in Python:

Utilize key-value pairs for string formatting.

# Example
person_info = {'name': 'Eve', 'age': 35}
formatted_string = "Name: {name}, Age: {age}".format_map(person_info)

Using f-Strings with Dictionaries in Python:

f-Strings provide a concise way to format strings using expressions.

# Example
person_info = {'name': 'Charlie', 'age': 40}
f_string = f"Name: {person_info['name']}, Age: {person_info['age']}"

Formatting Strings with format() and Dictionaries:

The format() method can be applied to dictionaries for string formatting.

# Example
person_info = {'name': 'Grace', 'age': 22}
formatted_string = "Name: {name}, Age: {age}".format(**person_info)

Dynamic String Formatting with Python Dict:

Dynamically create formatted strings based on dictionary values.

# Example
key_to_format = 'name'
person_info = {'name': 'David', 'age': 27}
dynamic_formatted_string = "Value: {}".format(person_info.get(key_to_format, 'N/A'))

Inserting Dictionary Values into Strings in Python:

Insert dictionary values into strings using various methods.

# Example
person_info = {'name': 'Fiona', 'age': 33}
inserted_string = "Name: %(name)s, Age: %(age)d" % person_info

String Interpolation with Dictionary Keys in Python:

Interpolate dictionary keys directly into strings.

# Example
person_info = {'name': 'George', 'age': 45}
interpolated_string = "Name: {name}, Age: {age}".format(**person_info)

Formatted String Literals (f-Strings) with Dictionaries:
- f-Strings provide a concise and readable way to format strings with dictionary values.
```
# Example
person_info = {'name': 'Helen', 'age': 29}
f_string = f"Name: {person_info['name']}, Age: {person_info['age']}"
```