diff --git a/utils/slither_format/format_constant_function.py b/utils/slither_format/format_constant_function.py
index 13bc725a0..d31f2b47c 100644
--- a/utils/slither_format/format_constant_function.py
+++ b/utils/slither_format/format_constant_function.py
@@ -13,7 +13,7 @@ class FormatConstantFunction:
                 if not Found:
                     for function in contract.functions:
                         if contract.name == element['contract']['name'] and function.name == element['name']:
-                            FormatConstantFunction.create_patch(slither, patches, element['source_mapping']['filename_absolute'], ["view","pure","constant"], "", int(function.parameters_src.split(':')[0]), int(function.returns_src.split(':')[0]))
+                            FormatConstantFunction.create_patch(slither, patches, element['source_mapping']['filename_absolute'], ["view","pure","constant"], "", int(function.parameters_src.source_mapping['start']), int(function.returns_src.source_mapping['start']))
                             Found = True
 
     @staticmethod
diff --git a/utils/slither_format/format_external_function.py b/utils/slither_format/format_external_function.py
index 389b0d06b..d9c826e9e 100644
--- a/utils/slither_format/format_external_function.py
+++ b/utils/slither_format/format_external_function.py
@@ -14,7 +14,7 @@ class FormatExternalFunction:
                             # to external because external function parameters are allocated in calldata region which is
                             # non-modifiable. See https://solidity.readthedocs.io/en/develop/types.html#data-location
                             if not FormatExternalFunction.function_parameters_written(function):
-                                FormatExternalFunction.create_patch(slither, patches, element['source_mapping']['filename_absolute'], "public", "external", int(function.parameters_src.split(':')[0]), int(function.returns_src.split(':')[0]))
+                                FormatExternalFunction.create_patch(slither, patches, element['source_mapping']['filename_absolute'], "public", "external", int(function.parameters_src.source_mapping['start']), int(function.returns_src.source_mapping['start']))
                                 Found = True
                                 break
 
diff --git a/utils/slither_format/format_naming_convention.py b/utils/slither_format/format_naming_convention.py
index 72b975497..7b868cad7 100644
--- a/utils/slither_format/format_naming_convention.py
+++ b/utils/slither_format/format_naming_convention.py
@@ -168,13 +168,13 @@ class FormatNamingConvention:
                     for m  in function.modifiers:
                         if (m.name == name):
                             in_file_str = slither.source_code[in_file]
-                            old_str_of_interest = in_file_str[int(function.parameters_src.split(':')[0]):int(function.returns_src.split(':')[0])]
+                            old_str_of_interest = in_file_str[int(function.parameters_src.source_mapping['start']):int(function.returns_src.source_mapping['start'])]
                             (new_str_of_interest, num_repl) = re.subn(name, name[0].lower()+name[1:],old_str_of_interest,1)
                             if num_repl != 0:
                                 patch = {
                                     "detector" : "naming-convention (modifier uses)",
-                                    "start" : int(function.parameters_src.split(':')[0]),
-                                    "end" : int(function.returns_src.split(':')[0]),
+                                    "start" : int(function.parameters_src.source_mapping['start']),
+                                    "end" : int(function.returns_src.source_mapping['start']),
                                     "old_string" : old_str_of_interest,
                                     "new_string" : new_str_of_interest
                                 }