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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 avail_modules(desc=False):
    '''
    List available modules in registered Powershell module repositories.

    :param desc: If ``True``, the verbose description will be returned.
    :type  desc: ``bool``

    CLI Example:

    .. code-block:: bash

        salt 'win01' psget.avail_modules
        salt 'win01' psget.avail_modules desc=True
    '''
    cmd = 'Find-Module'
    modules = _pshell(cmd)
    names = []
    if desc:
        names = {}
    for module in modules:
        if desc:
            names[module['Name']] = module['Description']
            continue
        names.append(module['Name'])
    return names