Python Template

Python Template Class

In Python, the template class is used for creating simplified syntax to specify an output. The format of the template uses $ symbol followed by placeholders names and valid Identifiers. The placeholder name surrounded by braces allows it to add more alphanumeric letters without the presence of intervening spaces.

How Template Work in Python

• The template class first uses a string as a template. A placeholder variable name is used within the string preceding with a $ symbol . The dollar symbol here depicts the presence of a placeholder. To write $ itself in the code, $$ is used.
• substitute() method is used to substitute value into the template using a dictionary. It is ensured that the key is in the dictionary and matches the placeholder name. The template is hence returned with all the values rather than the placeholder.
• We follow the convention of naming the placeholder variable name as the variable naming in Python.

Substitution Roles

• A substitution placeholder is named using $identifierthat maps a mapping key of identifier.
• The $ followed by the first non-identifier character terminates the specification of placeholder.
• $$ is replaced with a single $ and is considered an escape.

Implementation of Template

To implement a template, write the following code:

Output:

Explanation:

x in the code is replaced by Abhipsa

Python Template Data Output Program

Lets write a code to see the implementation of Python Template data as an output program.

Output:

Python Template Errors

In Python, following are the two types of errors:

1. Key Error: When the template is deprived of the value for a placeholder it shows No Placeholder Match.
2. Value Error: When the placeholder starts with an invalid character, it shows Bad Placeholder.

Handling Error

• In Python, the template provides a safe_substitute() method that gives back a string to handle the above mentioned errors.
• It leaves the placeholders as it is if it finds that the data is missing. The placeholders are returned if any error prevails. For better understanding, let's take an example:

Output:

Here, the $symbol still prevails.

Read More:

• Types of Errors in Python.