What are Lambda expressions in python?

Lambda expressions:
  • Lambda functions are single-expression functions that are not necessarily bound to a name.
  • Lambda expression is an anonymous function.
  • Executing a lambda function evaluates its expression and then automatically returns its result. So there is always an implicit return statement.
  • It's a shorthand that allows us to write a method in the same place we are going to use it.
  • The difference between lambdas and regular function definitions is that lambda functions are restricted to a single expression. This means a lambda function can't use statements or annotations, not even a return statement.
  • Example:
double = lambda x: x * 2
double(2) # it will return 4

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