numpy dtypes and fits keywords
bool: 'L',
uint8: 'B',
int16: 'I',
int32: 'J',
int64: 'K',
float32: 'E',
float64: 'D',
complex64: 'C',
complex128: 'M'
bool: 'L',
uint8: 'B',
int16: 'I',
int32: 'J',
int64: 'K',
float32: 'E',
float64: 'D',
complex64: 'C',
complex128: 'M'