如何完成此代码以计算地球的“逃逸速度”？

问：

我知道 ！= 应该更改为 ==，但是当我再次运行代码时，我认为它试图告诉我整个 [if mass == Decimal（'0'） or radius == Decimal（'0'）：] 命令不正确。我知道这段代码中至少还有一个语法错误，但是如果不先修复 [if mass == Decimal （'0'） or radius == Decimal（'0'）：] 命令，我无法让 python 告诉我它是什么。

decimal import *

GRAVITATIONAL_CONSTANT = Decimal('6.67384E-11')


# Credit to http://codingwithnumbers.blogspot.com/ for this function
def escape_velocity(mass, radius):
    '''Calculates the delta-V escape velocity.

    Returns delta-V in meters per second for the escape
    velocity for a given object given its mass in kilograms
    and its radius in meters.'''

    #IMPORTANT: mass and radius should be checked to see if they are exactly equal to zero, using the correct comparison operator
    # If either are exactly equal to 0, this function will return None
        if mass != Decimal('0') or radius != Decimal('0'):
    return None

    # Calculate the result using correct formulas
    # NOTE: Syntax errors on one line may mistakenly cause an error to appear on another
    result = Decimal((2 * GRAVITATIONAL_CONSTANT * mass) / radius
        result = result.sqrt()

        return result


earth_mass_in_kg = Decimal('5.9736E24')
earth_radius_in_meters = Decimal('6371000')

    print("The escape velocity of Earth is {} m/s".format(round(escape_velocity(earth_mass_in_kg, earth_radius_in_meters))))