Self-concatenation

"In Python, strings can be multiplied by numbers. Concatenating strings to numbers doesn't work You can't use the plus sign (+) between a string and a number in Python: You can use the plus sign to add two numbers: Or to concatenate two strings: But it doesn't work between strings and numbers. More on that: Fixing TypeError: can only concatenate str (not "int") to str."

"You can think of this as self-concatenation. We're concatenating this string to itself a specific number of times: Self-concatenation only works with integers You can only self-concatenate a string using integers: It wouldn't really make sense for strings to be multiplied a non-integer number of times. Interestingly, negative numbers do work for self-concatenation, they'll just always give an empty string: Which is also what happens when you multiply a string by 0:"

Python does not allow concatenating a string and a number with the + operator; using + works only between two numbers or two strings and otherwise raises a TypeError. Strings can be multiplied by integers to produce repeated concatenation of the same string. Only integer multipliers are supported; non-integer multipliers are not meaningful. Multiplying by zero or by a negative integer yields an empty string. Other sequence types that support concatenation, such as lists, tuples, and byte strings, also support repetition. Repetition can produce repeated characters or initialize lists with default values. Repetition does not create copies beyond the resulting object itself.

Read at Pythonmorsels