def startswith(self, prefix: StringVar | str) -> BooleanVar:
        """Check if the string starts with a prefix.

        Args:
            prefix: The prefix.

        Returns:
            The string starts with operation.
        """
        if not isinstance(prefix, (StringVar, str)):
            raise_unsupported_operand_types("startswith", (type(self), type(prefix)))
        return string_starts_with_operation(self, prefix)
Check if the string starts with a prefix.

        Args:
            prefix: The prefix.

        Returns:
            The string starts with operation.
        
reflex/vars/sequence.py