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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 mount_path(source, target, bind=False):
 """ Subprocess call to mount dev at path. """

        cmd = ['mount']
        if bind:
            cmd.append('--bind')
        cmd.append(source)
        cmd.append(target)
        r = util.subp(cmd)
        if r.return_code != 0:
            raise MountError('Could not mount docker container:\n' +
                             ' '.join(cmd) + '\n%s' %
                             r.stderr.decode(sys.getdefaultencoding()))