Correct TestEran_Port function to properly test port()function
```func TestEran_Port(t *testing.T) {
	cases := []struct {
		subNetwork string
		nodes      map[string]map[string]map[string]string
		name       string
		tnPort     string
		tnPort2    string
	}{
		{
			subNetwork: "Shymkent",
			nodes:      map[string]map[string]map[string]string{
				"ERBS_41001_BCUKGU_2_KKT": {
					"EUtranCellData": {
						"Name":"ERBS_41001_BCUKGU_2_KKT",
					},
				},
			},
			name:       "ERBS_41001_BCUKGU_1_KKT",
			tnPort:     "TN_IDL_D",
			tnPort2:    "",
		},
		{
			subNetwork: "Shymkent",
			nodes:      map[string]map[string]map[string]string{
				"GRBS_41001_BCUKGU_1_KKT": {
					"EUtranCellData": {
						"Name":"GRBS_41001_BCUKGU_1_KKT",
					},
				},
			},
			name:       "ERBS_41001_BCUKGU_1_KKT",
			tnPort:     "TN_IDL_C",
			tnPort2:    "",
		},
		{
			subNetwork: "Shymkent",
			nodes:      map[string]map[string]map[string]string{
				"ERBS_41001_BCUKGU_1_KKT": {
					"EUtranCellData": {
						"Name":"ERBS_41001_BCUKGU_1_KKT",
					},
				},
			},
			name:       "GRBS_41001_BCUKGU_1_KKT",
			tnPort:     "TN_IDL_C",
			tnPort2:    "",
		},
		{
			subNetwork: "Almaty",
			nodes:      map[string]map[string]map[string]string{
				"ERBS_01001_BCUKGU_1_KKT": {
					"EUtranCellData": {
						"Name":"ERBS_01001_BCUKGU_1_KKT",
						},
				},
			},
			name:       "GRBS_01001_BCUKGU_1_KKT",
			tnPort:     "TN_IDL_C",
			tnPort2:    "",
		},
		{
			subNetwork: "Almaty",
			nodes:      map[string]map[string]map[string]string{
				"GRBS_01001_BCUKGU_1_KKT": {
					"EUtranCellData": {
						"Name":"GRBS_01001_BCUKGU_1_KKT",
					},
				},
			},
			name:       "ERBS_01001_BCUKGU_1_KKT",
			tnPort:     "TN_A",
			tnPort2:    "",
		},
		{
			subNetwork: "Almaty",
			nodes:      map[string]map[string]map[string]string{
				"ERBS_01001_BCUKGU_2_KKT": {
					"EUtranCellData": {
						"Name":"ERBS_01001_BCUKGU_2_KKT",
					},
				},
			},
			name:       "ERBS_01001_BCUKGU_1_KKT",
			tnPort:     "TN_B",
			tnPort2:    "",
		},
		{
			subNetwork: "Shymkent",
			nodes:      map[string]map[string]map[string]string{
				"ERBS_41001_BCUKGU_1_KKT": {
					"EUtranCellData": {
						"Name":"ERBS_41001_BCUKGU_1_KKT",
					},
				},
				"ERBS_41001_BCUKGU_2_KKT": {
					"EUtranCellData": {
						"Name":"ERBS_41001_BCUKGU_2_KKT",
					},
				},
			},
			name:       "GRBS_01001_BCUKGU_1_KKT",
			tnPort:     "TN_IDL_C",
			tnPort2:    "TN_IDL_D",
		},
		{
			subNetwork: "Shymkent",
			nodes:      map[string]map[string]map[string]string{
				"GRBS_41001_BCUKGU_1_KKT": {
					"EUtranCellData": {
						"Name":"GRBS_41001_BCUKGU_1_KKT",
					},
				},
				"ERBS_41001_BCUKGU_1_KKT": {
					"EUtranCellData": {
						"Name":"ERBS_41001_BCUKGU_1_KKT",
					},
				},
			},
			name:       "ERBS_41001_BCUKGU_2_KKT",
			tnPort:     "TN_IDL_D",
			tnPort2:    "TN_IDL_C",
		},
		{
			subNetwork: "Almaty",
			nodes:      map[string]map[string]map[string]string{
				"GRBS_01001_BCUKGU_1_KKT": {
					"EUtranCellData": {
						"Name":"GRBS_01001_BCUKGU_1_KKT",
					},
				},
				"ERBS_01001_BCUKGU_2_KKT": {
					"EUtranCellData": {
						"Name":"ERBS_01001_BCUKGU_2_KKT",
					},
				},
			},
			name:       "ERBS_01001_BCUKGU_1_KKT",
			tnPort:     "TN_B",
			tnPort2:    "TN_A",
		},
		{
			subNetwork: "Almaty",
			nodes:      map[string]map[string]map[string]string{
				"ERBS_401001_BCUKGU_1_KKT": {
					"EUtranCellData": {
						"Name":"ERBS_01001_BCUKGU_1_KKT",
					},
				},
				"ERBS_01001_BCUKGU_2_KKT": {
					"EUtranCellData": {
						"Name":"ERBS_01001_BCUKGU_2_KKT",
					},
				},
			},
			name:       "GRBS_01001_BCUKGU_1_KKT",
			tnPort:     "TN_IDL_C",
			tnPort2:    "TN_IDL_D",
		},
	}

	for _, c := range cases {
		testName := fmt.Sprintf(c.subNetwork, )
		t.Run(testName, func(t *testing.T) {
			elasticran := EranConnection{
				SubNetwork: SubNetwork{
					Name: c.subNetwork,
				},
			}
			
			elasticran.port()

			if elasticran.TnPort != c.tnPort {
				t.Errorf("[%s] Expected TnPort to be %s, but got %s", testName, c.tnPort, elasticran.TnPort)
			}

			if elasticran.TnPort2 != c.tnPort2 {
				t.Errorf("[%s] Expected TnPort2 to be %s, but got %s", testName, c.tnPort2, elasticran.TnPort2)
			}
		})
	}
}

// connection initiates EranConnection default BBU connection type
func (elasticran *EranConnection) port() {
	name := elasticran.ENodeB.Cellular.Name
	subNetwork := elasticran.SubNetwork.Name
	nodes := elasticran.Nodes
	
	if nodes.Count() == 1 {
		nodesname := nodes.Names()
		elasticran.TnPort2 = ""
		if strings.HasPrefix(name, "GRBS") {
			elasticran.TnPort = "TN_IDL_C"
		} else if strings.HasPrefix(name, "ERBS") && strings.Contains(name, "_1_") && strings.HasPrefix(nodesname[0], "GRBS") {
			if subNetwork == "Shymkent" {
				elasticran.TnPort = "TN_IDL_C"
			} else {
				elasticran.TnPort = "TN_A"
			}
		} else if strings.HasPrefix(name, "ERBS") && strings.Contains(name, "_1_") {
			if subNetwork == "Shymkent" {
				elasticran.TnPort = "TN_IDL_D"
			} else {
				elasticran.TnPort = "TN_B"
			}
		} else if strings.HasPrefix(name, "ERBS") && strings.Contains(name, "_2_") {
			if subNetwork == "Shymkent" {
				elasticran.TnPort = "TN_IDL_C"
			} else {
				elasticran.TnPort = "TN_A"
			}
		}
	} else if nodes.Count() == 2 {
		if strings.HasPrefix(name, "GRBS") {
			elasticran.TnPort = "TN_IDL_C"
			elasticran.TnPort2 = "TN_IDL_D"
		} else if strings.HasPrefix(name, "ERBS") {
			if subNetwork == "Shymkent" {
				elasticran.TnPort = "TN_IDL_D"
				elasticran.TnPort2 = "TN_IDL_C"
			} else {
				elasticran.TnPort = "TN_B"
				elasticran.TnPort2 = "TN_A"
			}
		}
	}
}```