from typing import Dict


def get_email_to_names_table(email_to_names_filename: str) -> Dict[str, str]:
    """Get a mapping of emails to names from the input file.

    Args:
        email_to_names_filename: Path to file with emails and corresponding
          names, where each email-name pair is on a separate line and each line
          looks like the following:
                email@example.com,Name

    Returns:
        A dict mapping emails to names.
    """

    email_to_names_table = {}
    with open(email_to_names_filename, "r") as email_to_names_file:
        for line in email_to_names_file:
            email, name = line.rstrip().split(sep=",")
            assert email not in email_to_names_table
            email_to_names_table[email] = name
    return email_to_names_table