Cannot assign string with single quote in golang

I am learning go and when playing with string I noticed that if a string is in single quotes then golang is giving me an error but double quotes are working fine.

func main() {
    var a string
    a = 'hello' //will give error
    a = "hello" //will not give error
}

This is the error I get on my system:

illegal rune literal

While when I try to do the same on playground I am getting this error:

prog.go:9: missing '
prog.go:9: syntax error: unexpected name, expecting semicolon or newline or }
prog.go:9: newline in string
prog.go:9: empty character literal or unescaped ' in character literal
prog.go:9: missing '

I am not able to understand the exact reason behind this as in for example Python, Perl one can declare a string with both single and double quote.

In Go, '⌘' represents a single character (called a Rune), whereas "⌘" represents a string containing the character ⌘.

This is true in many programming languages where the difference between strings and characters is notable, such as C++ ¹.

Check out the "Code points, characters, and runes" section in the Go Blog on Strings

¹ Note that strings in Go are not null terminated \0 and instead represented by a pointer to their start and an integer length.