float

def float(
a: bool | float | int | str = ...,
/,
) -> float

float: interprets its argument as a floating-point number.

If x is a float, the result is x. if x is an int, the result is the nearest floating point value to x. If x is a string, the string is interpreted as a floating-point literal. With no arguments, float() returns 0.0.

float() == 0.0
float(1) == 1.0
float('1') == 1.0
float('1.0') == 1.0
float('.25') == 0.25
float('1e2') == 100.0
float(False) == 0.0
float(True) == 1.0
float("hello")   # error: not a valid number
float([])   # error