text: #include <cs50.h>
  #include <stdio.h>
  
  int main(void)
  {
      FILE *file = fopen("phonebook.csv", "a");
      if (file == NULL)
      {
          return 1;
      }
  
      char *name = get_string("Name: ");
      char *number = get_string("Number: ");
  
      fprintf(file, "%s, %s\n", name, number);
      fclose(file);
      
      return 0;
  }
  