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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 update(packages, env=None, user=None):
 """ Update conda packages in a conda env Attributes packages: list of packages comma delimited """

    packages = ' '.join(packages.split(','))
    cmd = _create_conda_cmd('update', args=[packages, '--yes', '-q'], env=env, user=user)
    return _execcmd(cmd, user=user)