def find_prot2(fasta_dict, re_str):
    '''Search through a dictionary of fasta entries using a regular expression'''

    # Import re module
    import re   # typically imported at top of module file

    # Create pattern object
    pattern = re.compile(re_str)          

    # Create empty list to store results
    result_list = []          

    # Iterate over all keys in dictionary
    for key in fasta_dict.keys():          

        # If the pattern matches, append to result_list
        if pattern.match(key):
            result_list.append(key)          

    return result_list