Rename fields in a GDB feature class

rename_fields.py

#path to feature class
dataset = r"\\some\directory.gdb\feature_class"

#store new field names and new field aliases in a dictionary
#key is current field name, value is new field name
rename_fields = {
    "current_name1":"new_name1",
    "current_name2":"new_name2" 
}

#rename the fields
for key, value in rename_fields.items():
    print("renaming {0} to {1}".format(key,value))
    arcpy.AlterField_management(dataset,field=key, new_field_name=value)