def find_line_of_residue(reslist, resinumber):
    """
    Returns the line number where residue n appears in the reslist.
    :param reslist: res file as list like:
                    ['C1 1 -0.00146 0.26814 0.06351 11.00 0.05',
                    'RESI 4 BENZ',
                    'C2 1 -1.13341 -0.23247 -0.90730 11.00 0.05',]
    :type reslist: list of lists
    :param resinumber: residue number
    :type resinumber: string
    :return n: integer
    :return line: string
    >>> find_line_of_residue(['REM TEST', 'C1 1 -0.00146 0.26814 0.06351 11.00 0.05', \
        'RESI 4 BENZ', 'C2 1 -1.13341 -0.23247 -0.90730 11.00 0.05'], "4")
    [2, 'RESI 4 BENZ']
    """
    for n, line in enumerate(reslist):
        if line.upper().startswith('RESI'):
            if line.split()[1] == str(resinumber):
                return [n, line]