Python parentheses () and brackets []

In Python, the parentheses () represent the tuple tuple data type, which is an immutable sequence.

>>> A = (A/b)>>> A (1, 2, 3)>>> a = (1,)         #  Tuple of a value >>> a (1,)>>>, (in.)                    # a tuple of values >>> 5555                       # without commas becomes a separate number >>> ()        ()                        # Empty tuple    

In Python, the brackets [] represent the list data type, and the list is a mutable sequence.

Note: Whether in tuples or lists, a tuple or list of values can be followed by commas, or without

>>> a = (1,)>>> A (1,)>>> Len (a)1>>> b = [1  ,]>>> b[1]>>> len (b)1

In fast rcnn code, __c.train. SCALES = (600,) actually represents a tuple, not an XY coordinate

Python parentheses () and brackets []