import math


def get_magnitude_2D(vector_2D):
    """
    Args:
        vector_2D (list): eg [0,0] vector
        
    Returns:
        float: The magnitude of the vector.
    """
    return math.sqrt( (vector_2D[0] * vector_2D[0]) + (vector_2D[1] * vector_2D[1]) )