def flatten_list_prime(l):
    """
    Flattens a list so that all prime numbers in embedded lists are 
        returned in a flat list
    
    Parameters:
        - l: a list of numbers; largest prime cannot be greater than 1000
    
    Returns:
        - flat_l: a flat list that has all the prime numbers in l
        
    Examples:
        a = [[2, 3, 4, 5], 19, [131, 127]]
        flatten_list_prime(a) # returns [2, 3, 5, 19, 131, 127]
    """
    
    # Raise error if input not a list
    if type(l) != list:
        raise TypeError("Input must be a list")
        
    #set list of predefined list of prime numbers less than 1000
    prime = [2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,
        89,97,101,103,107,109,113,127,131,137,139,149,151,157,163,167,173,179,
        181,191,193,197,199,211,223,227,229,233,239,241,251,257,263,269,271,
        277,281,283,293,307,311,313,317,331,337,347,349,353,359,367,373,379,
        383,389,397,401,409,419,421,431,433,439,443,449,457,461,463,467,479,
        487,491,499,503,509,521,523,541,547,557,563,569,571,577,587,593,599,
        601,607,613,617,619,631,641,643,647,653,659,661,673,677,683,691,701,
        709,719,727,733,739,743,751,757,761,769,773,787,797,809,811,821,823,
        827,829,839,853,857,859,863,877,881,883,887,907,911,919,929,937,941,
        947,953,967,971,977,983,991,997]          

    l_copy = l[:]
    
    # flatten list in the loop
    flat_l = []
    while len(l_copy) >= 1:
        elem = l_copy.pop()
        if not isinstance(elem, int) and not isinstance(elem, list):
            raise TypeError("Input must be list of intergers")
        if isinstance(elem, list):
            l_copy.extend(elem)
        else:
            if elem >= 1000:
                raise ValueError("Input values exceed 1000. Please limit range of input values to less than 1000.")                
            if elem in prime:
                flat_l.append(elem)
    flat_l.sort()
    return flat_l