def get_starting_model(interaction_dict, verbose=False):
    """Returns as a starting model one of the CustomModel of the chain with more recorded interactions"""
    if verbose:
        print("Selecting best interaction from where to start modeling...")
    max_len = 0
    interaction_key = None
    for key in interaction_dict:
        length = len(interaction_dict[key])
        if length > max_len:  # If a chain has more interactions
            max_len = length  # Updates maximum interaction umber
            interaction_key = key  # Updates maximum interaction chain key
    inter_tple = next(iter(interaction_dict[interaction_key]))  # Gets an interaction tuple of the chain
    # with more interactions
    if verbose:
        print("First two chains added")
    return interaction_dict[interaction_key][inter_tple][0].parent.copy()