function acceptPropAsAcceptAttr(accept) {
  if (isDefined(accept)) {
    return (
      Object.entries(accept)
        .reduce((a, [mimeType, ext]) => [...a, mimeType, ...ext], [])
        // Silently discard invalid entries as pickerOptionsFromAccept warns about these
        .filter((v) => isMIMEType(v) || isExt(v))
        .join(",")
    );
  }

  return undefined;
}
Convert the `{accept}` dropzone prop to an array of MIME types/extensions.
@param {AcceptProp} accept
@returns {string}