> For the complete documentation index, see [llms.txt](https://quantitative-algorithms-by-max-h.gitbook.io/predator-trading-system/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://quantitative-algorithms-by-max-h.gitbook.io/predator-trading-system/overview/predator-script-documentation/predator-script/commands/utility.md).

# Utility

**ImportCommand**

Dynamically imports a list of modules at runtime and returns a dictionary of the imported modules.

* **Constructor Parameters:**
  * `*modules (str)`: A variable number of module names to be imported.
* **Methods:**
  * `execute(self, data_provider=None)`: Attempts to import each module in `self.modules`. If successful, adds the module to `self.imported_modules` and returns this dictionary. Prints a success message for each imported module, and an error message if a module cannot be imported.
* **Returns:** A dictionary with module names as keys and the corresponding imported module objects as values.

**Example Usage:**

```python
import_cmd = ImportCommand('pandas', 'numpy')
imported_modules = import_cmd.execute()
```

***

**SMACrossCommand**

Checks for a crossover between a short-period SMA and a long-period SMA over a specified time range.

* **Constructor Parameters:**
  * `start (str)`: The start date for the calculation.
  * `end (str)`: The end date for the calculation.
  * `short_period (int)`: The number of periods for the short-term SMA. Default is 50.
  * `long_period (int)`: The number of periods for the long-term SMA. Default is 200.
* **Methods:**
  * `execute(self, data_provider)`: Calculates the SMA for the short and long periods and identifies crossovers.
* **Returns:** A series indicating where crossovers occur.

**Example Usage:**

```python
sma_cross_command = SMACrossCommand(start="2023-01-01", end="2023-06-30", short_period=50, long_period=200)
crossover_result = sma_cross_command.execute(data_provider)
```

***

**PriceLevelCheckCommand**

Checks whether the closing prices of a security cross a specified price level during a given time range.

* **Constructor Parameters:**
  * `level (float)`: The price level to check against.
  * `start (str)`: The start date for the calculation.
  * `end (str)`: The end date for the calculation.
* **Methods:**
  * `execute(self, data_provider)`: Retrieves the closing prices and checks where they cross the specified price level.
* **Returns:** A series indicating where price level crossings occur.

**Example Usage:**

```python
price_check_command = PriceLevelCheckCommand(level=150, start="2023-01-01", end="2023-06-30")
level_cross_result = price_check_command.execute(data_provider)
```

***

**TimeBasedCommand**

* **Description:** Executes a given command at a specified time.
* **Constructor Parameters:**
  * `command (Command)`: The command to be executed.
  * `execution_time (datetime.time)`: The time at which the command should be executed.
* **Methods:**
  * `execute(self, data_provider)`: Checks the current time and executes the command if the current time is greater than or equal to the specified `execution_time`.
* **Returns:** The result of the command execution, or `None` if the time condition is not met.

**Example Usage:**

```python
from datetime import time
time_based_command = TimeBasedCommand(command=SomeCommand(), execution_time=time(14, 30))
result = time_based_command.execute(data_provider)
```