python_3.py

def fasta_names_to_list(fasta_filename):
    '''Extract FASTA IDs from file to list'''
    
    names = []

    # Open fasta file
    fasta_file = open(fasta_filename)
        
    # Iterate over lines
    for line in fasta_file:

        # Add to list if line starts with '>'
        # Call to fasta_label_to_id to extract id from line
        if line.startswith('>'):
            names.append(fasta_label_to_id(line))
    
    return names