How to use the grommet-icons.FormUp function in grommet-icons

background: {
          dark: 'dark-2',
          light: 'light-2'
        }
      },
      header: {
        border: { side: 'bottom', size: 'small' },
        pad: { horizontal: 'small', vertical: 'xsmall' },
        background: {
          dark: 'dark-1',
          light: 'light-1'
        }
      },
      icons: {
        ascending: _grommetIcons.FormDown,
        contract: _grommetIcons.FormUp,
        descending: _grommetIcons.FormUp,
        expand: _grommetIcons.FormDown
      },
      resize: {
        border: {
          side: 'right',
          color: {
            dark: 'border-dark',
            light: 'border-light'
          }
        }
      }
    },
    // drop: {
    //   maxHeight: undefined,
    // },

dark: 'dark-2',
          light: 'light-2'
        }
      },
      header: {
        border: { side: 'bottom', size: 'small' },
        pad: { horizontal: 'small', vertical: 'xsmall' },
        background: {
          dark: 'dark-1',
          light: 'light-1'
        }
      },
      icons: {
        ascending: _grommetIcons.FormDown,
        contract: _grommetIcons.FormUp,
        descending: _grommetIcons.FormUp,
        expand: _grommetIcons.FormDown
      },
      resize: {
        border: {
          side: 'right',
          color: {
            dark: 'border-dark',
            light: 'border-light'
          }
        }
      }
    },
    // drop: {
    //   maxHeight: undefined,
    // },
    formField: {

medium: baseSpacing * 8 + 'px', // 192
          large: baseSpacing * 16 + 'px', // 384
          xlarge: baseSpacing * 32 + 'px', // 768
          full: '100%'
        }
      },
      text: {
        color: {
          dark: '#f8f8f8',
          light: textColor
        }
      }
    },
    accordion: {
      icons: {
        collapse: _grommetIcons.FormUp,
        expand: _grommetIcons.FormDown
        // color: { dark: undefined, light: undefined },
      }
    },
    anchor: {
      textDecoration: 'none',
      fontWeight: 600,
      color: {
        dark: '#6194EB',
        light: '#6194EB'
      }
    },
    button: {
      border: {
        // color: { dark: undefined, light: undefined }
        width: borderWidth + 'px',