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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 symlink_list(load):
    '''
    Return a dict of all symlinks based on a given path on the Master
    '''
    if 'env' in load:
        # "env" is not supported; Use "saltenv".
        load.pop('env')

    ret = {}
    if load['saltenv'] not in __opts__['file_roots'] and '__env__' not in __opts__['file_roots']:
        return ret

    if 'prefix' in load:
        prefix = load['prefix'].strip('/')
    else:
        prefix = ''

    symlinks = _file_lists(load, 'links')
    return dict([(key, val)
                 for key, val in six.iteritems(symlinks)
                 if key.startswith(prefix)])