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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 help(self, command=None):
    '''help prints the general function help, or help for a specific command

        Parameters
        ==========   
        command: the command to get help for, if none, prints general help

    '''
    from spython.utils import check_install
    check_install()

    cmd = ['singularity','--help']
    if command != None:
        cmd.append(command)
    help = self._run_command(cmd)
    return help