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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def remove_reference_line_marker(line):
 """Trim a reference line's 'marker' from the beginning of the line. @param line: (string) - the reference line. @return: (tuple) containing two strings: + The reference line's marker (or if there was not one, a 'space' character. + The reference line with it's marker removed from the beginning. """

    # Get patterns to identify reference-line marker patterns:
    marker_patterns = get_reference_line_numeration_marker_patterns()
    line = line.lstrip()

    marker_match = regex_match_list(line, marker_patterns)

    if marker_match is not None:
        # found a marker:
        marker_val = marker_match.group(u'mark')
        # trim the marker from the start of the line:
        line = line[marker_match.end():].lstrip()
    else:
        marker_val = u" "
    return (marker_val, line)