Create new structure for Indiana dependent exemptions

Fixes PolicyEngine#5223

policyengine_us/parameters/gov/states/in/tax/income/exemptions/base/dependent.yaml

@@ -1,11 +1,11 @@
-description: Indiana provides this base exemption amount.
+description: Indiana provides this base exemption amount for dependent.
 values:
   2021-01-01: 1_000
 
 metadata:
   period: year
   unit: currency-USD
-  label: Indiana exemptions base amount
+  label: Indiana exemptions base amount - dependent 
   reference:
     - title: IC 6-3-1-3.5 "Adjusted gross income" (a)(3)-(4)
       href: http://iga.in.gov/legislative/laws/2021/ic/titles/006#6-3-1-3.5

policyengine_us/variables/gov/states/in/tax/income/exemptions/in_base_exemptions.py

@@ -10,6 +10,22 @@ class in_base_exemptions(Variable):
     reference = "http://iga.in.gov/legislative/laws/2021/ic/titles/006#6-3-1-3.5"  # (a)(3)-(4)
     defined_for = StateCode.IN
 
+
     def formula(tax_unit, period, parameters):
         p = parameters(period).gov.states["in"].tax.income.exemptions
-        return tax_unit("tax_unit_size", period) * p.base.amount
+	    filing_status = tax_unit("filing_status", period)
+
+	# Personal exemptions
+	    personal_exemptions = p.base.amount[filing_status]
+
+
+	# Dependent exemptions
+        dependents = tax_unit(
+            "tax_unit_dependents", period
+        )  # Total the number of dependents
+
+        dependent_exemptions = dependents * p.base.dependent
+
+
+        # total exemptions
+        return personal_exemptions + dependent_exemptions