from 
from math import log, e, sin, cos
from run_tests import close_enough, run_test, run_test_float
## you can now use log(x) for the natural log of x.
## You can only use the imported functions that I specify.
def greet(name):
    """prec:  name is a keyword argument with default value "Stranger"
    postc: returns the string Hello, name!"""  
    return "Hello"
def log_base(x, b):
    """prec:  x > 0 and b > 0 is a keyword argument
    postc: use the change-of-base formula to compute 
    the logarithm of x with base b.  The default is that
    the natural log of x is returned."""
    return 0
def truncate(s, n):
    """prec:  s is a string, n is a nonnegative integer
    and a keyword argument.  if len(x) > s return s; otherwise
    truncate at n.  By default, n = 3."""
    return ""
def protean_sin(x, radians):
    """prec: x is a number, radians is a boolean and a
    keyword argument.  
    postc: returns sin(x) using radians if radians is True
    and sin(x) in degrees if radians is false.
    The default is True"""
    return 0
def protean_asin(x, radians):
    """prec: x is a number, -1 <= x <= 1.
    radians is a keyword argument.  
    postc: returns sin(x) using radians if radians is True
    and arcsin(x) in degrees if radians is false.
    The default is True."""
    return 0
def main():