TS error when using prop with ThemedStyledComponentsModule

I'm trying to use prop within ifProp, but getting an error that:

```
[ts]
Argument of type '(props?: Props) => Props[keyof Props]' is not assignable to parameter of type 'Interpolation>'.
Type '(props?: Props) => Props[keyof Props]' is not assignable to type 'InterpolationFunction>'.
Type 'ThemeInterface' is not assignable to type 'Interpolation>'.
Type 'ThemeInterface' is not assignable to type 'ReadonlyArray | InterpolationFunction> | ReadonlyArray>>>'.
Property 'length' is missing in type 'ThemeInterface'. [2345]
```

```
interface SpaceProps {
around?: string;
bottom?: string;
left?: string;
right?: string;
top?: string;
}

export const Space = styled.div`
${ifProp(
'around',
css`
margin: ${prop('around')}em;
`
)};
${ifProp(
'top',
css`
margin-top: ${prop('top')}em;
`
)};
${ifProp(
'right',
css`
margin-right: ${prop('right')}em;
`
)};
${ifProp(
'bottom',
css`
margin-bottom: ${prop('bottom')}em;
`
)};
${ifProp(
'left',
css`
margin-left: ${prop('left')}em;
`
)};
`;
```

I'm assuming I'm doing something wrong, but can't quite pinpoint what the problem may be.